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N-1A
UBS SERIES FUNDS
2026-08-28
UBS Liquid Assets Government Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">To provide as high a level of current interest income as is consistent with maintaining liquidity and stability of principal.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
200
125
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Financial Services Inc. may charge other account fees for certain other features offered through its programs. Please contact your Financial Advisor for more information, including the timing of the assessment of any applicable fee to your account. Certain types of accounts are not subject to the above referenced program fees.</div>
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
0.0003
0
0.0004
0.0007
“Management fees” have been restated to reflect amounts for the current fiscal year.
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
7
23
40
90
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example does not reflect the above referenced program fees.</div>
Principal strategiesPrincipal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, the fund invests in a diversified portfolio of high quality, US government money market instruments and in related repurchase agreements.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities) in order to qualify as a “government money market fund” under federal regulations. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states. In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements. US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In deciding</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements.
US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In deciding</div><div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk: </span>Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk: </span>There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk: </span>Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk: </span>The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk: </span>Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk: </span>The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Prior to April 15, 2016, the fund was named UBS Liquid Assets Fund, and the fund operated under certain different investment policies. The fund’s preceding historical performance does not represent its current investment policies.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Liquid Assets Government Fund Annual Total Returns Total return
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.82%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.37%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during years shown—3Q 2021: 0.00% (Actual total return was 0.0034%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available by contacting your Financial Advisor at UBS Financial Services Inc. or by calling 1‑888‑793 8637 (Option #1).</div>
Total return
2026-06-30
0.0182
Best quarter
2023-12-31
0.0137
Worst quarter
2021-09-30
0.000034
1‑888‑793 8637
Average annual total returns (for the periods ended December 31, 2025)
0.0424
0.0320
0.0217
UBS RMA Government Money Market Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
175
175
100
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Financial Services Inc. may charge other account fees for certain other features offered through its programs. Please contact your Financial Advisor for more information, including the timing of the assessment of any applicable fee to your account.</div>
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0020
0.0048
0.0025
0.0023
0.0068
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
69
218
379
847
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund. Management fees are comprised of investment advisory and administration fees.</div> </td> </tr> </table>
This example does not reflect the above referenced program fees.
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, the fund invests in a diversified portfolio of high quality, US government money market instruments and in related repurchase agreements.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities) in order to qualify as a “government money market fund” under federal regulations. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states. The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements. US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements.
US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of</div><div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk: </span>Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk: </span>There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk:</span> Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk: </span>The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk: </span>Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk: </span>The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US withholding tax risk:</span> The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. However, there can be no assurance that all of the fund’s distributions will be exempt from US withholding tax.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS RMA Government Money Market Fund Annual Total Returns Total return (2017 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.51%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.21%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarters during years shown—2Q & 3Q 2020; 1Q & 3Q 2021; 1Q 2022: 0.00% (Actual total returns were 0.0025%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0151
Best quarter
2023-12-31
0.0121
Worst quarter
2022-03-31
0.000025
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0361
0.0275
2016-06-24
0.0184
UBS Select Government Institutional Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0
0.0018
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
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<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, the fund invests in a diversified portfolio of high quality, US government money market instruments and in related repurchase agreements.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities) in order to qualify as a “government money market fund” under federal regulations. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states. The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements. US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements.
US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In</div><div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The Fund’s sponsor is not required to reimburse the Fund for losses, and you should not expect that the sponsor will provide financial support to the Fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support</div><div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk:</span> Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US withholding tax risk:</span> The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. However, there can be no assurance that any or all of the fund’s distributions will be exempt from US withholding tax.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Select Government Institutional Fund Annual Total Returns Total return (2017 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.75%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.33%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarters during years shown—1Q, 2Q, & 3Q 2021: 0.00% (Actual total returns were 0.0025%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0175
Best quarter
2023-12-31
0.0133
Worst quarter
2021-09-30
0.000025
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0411
0.0312
2016-07-26
0.0218
UBS Select Treasury Institutional Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0
0.0018
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
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<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, under normal circumstances, the fund invests in a diversified portfolio of high quality, US Treasury money market instruments and in related repurchase agreements.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities) in order to qualify as a “government money market fund” under federal regulations. In addition, in order to be a “Treasury” fund, under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements. For purposes of this policy, repurchase agreements are those that are collateralized fully by securities issued by the US Treasury and cash. Under normal circumstances, the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in securities</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">issued by the US Treasury. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in securities issued by the US Treasury, the fund considers the possible loss of this tax advantage.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
In addition, in order to be a “Treasury” fund, under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements.
For purposes of this policy, repurchase agreements are those that are collateralized fully by securities issued by the US Treasury and cash. Under normal circumstances, the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in securities</div><div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">issued by the US Treasury. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in securities issued by the US Treasury, the fund considers the possible loss of this tax advantage.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The Fund’s sponsor is not required to reimburse the Fund for losses, and you should not expect that the sponsor will provide financial support to the Fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk: </span>Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Select Treasury Institutional Fund Annual Total Returns Total return
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.76%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.33%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarters during years shown—1Q, 2Q & 3Q 2021: 0.00% (Actual total returns were 0.0025%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0176
Best quarter
2023-12-31
0.0133
Worst quarter
2021-09-30
0.000025
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0411
0.0310
0.0204
UBS Select 100% US Treasury Institutional Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell Institutional Shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0.0001
0.0019
0.0001
0.0018
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your Institutional Shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
18
60
106
242
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver/expense reimbursement agreement for the first year only. The fund invests in securities through an underlying master fund, 100% US Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of 100% US Treasury Master Fund, including management fees allocated from 100% US Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, under normal circumstances, the fund invests exclusively in a diversified portfolio of high quality, US Treasury money market instruments and may also hold cash.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. In order to qualify as a “government money market fund” under federal regulations, the fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities); however, as noted above, the fund expects to further limit its investments, and under normal circumstances, the fund invests exclusively in a diversified portfolio of high quality, US Treasury money market instruments and may also hold cash. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some state. The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The Fund will generally hold a portion of its assets in cash for operational purposes.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The Fund’s sponsor is not required to reimburse the Fund for losses, and you should not expect that the sponsor will provide financial support to the Fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US withholding tax risk:</span> The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. However, there can be no assurance that any or all of the fund’s distributions will be exempt from US withholding tax.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied over its first calendar year of operations.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Select 100% US Treasury Institutional Fund Annual Total Returns Total Return of Institutional Shares (2025 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.75%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during year shown—3Q 2025: 1.03%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during year shown—4Q 2025: 0.94%</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0175
Best quarter
2025-09-30
0.0103
Worst quarter
2025-12-31
0.0094
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the period ended December 31, 2025)
0.0407
2024-03-13
0.0447
UBS Select Government Preferred Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0
0.0018
0.0004
0.0014
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
14
54
97
226
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver agreement for the first year only. The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, the fund invests in a diversified portfolio of high quality, US government money market instruments and in related repurchase agreements.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities) in order to qualify as a “government money market fund” under federal regulations. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states. The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements. US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements.
US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In</div><div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”),</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk:</span> Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US withholding tax risk:</span> The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. However, there can be no assurance that any or all of the fund’s distributions will be exempt from US withholding tax.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Select Government Preferred Fund Annual Total Returns Total return (2017 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.77%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.34%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarters during years shown—1Q, 2Q & 3Q 2021: 0.00% (Actual total returns were 0.0025%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0177
Best quarter
2023-12-31
0.0134
Worst quarter
2021-09-30
0.000025
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0416
0.0315
2016-06-28
0.0220
UBS Select Treasury Preferred Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0
0.0018
0.0004
0.0014
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
14
54
97
226
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver agreement for the first year only. The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, under normal circumstances, the fund invests in a diversified portfolio of high quality, US Treasury money market instruments and in related repurchase agreements.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities) in order to qualify as a “government money market fund” under federal regulations. In addition, in order to be a “Treasury” fund, under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements. For purposes of this policy, repurchase agreements are those that are collateralized fully by securities issued by the US Treasury and cash. Under normal circumstances, the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in securities issued by the US Treasury. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in securities issued by the US Treasury, the fund considers the possible loss of this tax advantage.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
In addition, in order to be a “Treasury” fund, under normal circumstances, the fund seeks to achieve its objective by investing at least 80% of its net assets (plus the amount of any borrowing for investment purposes) in securities issued by the US Treasury and in related repurchase agreements.
For purposes of this policy, repurchase agreements are those that are collateralized fully by securities issued by the US Treasury and cash. Under normal circumstances, the fund expects to invest substantially all of its assets in securities issued by the US Treasury and in related repurchase agreements. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases securities issued by the US Treasury and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in securities issued by the US Treasury. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in securities issued by the US Treasury, the fund considers the possible loss of this tax advantage.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk: </span>Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over the various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Select Treasury Preferred Fund Annual Total Returns Total return
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.78%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.34%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarters during years shown—1Q, 2Q & 3Q 2021: 0.00% (Actual total returns were 0.0025%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0178
Best quarter
2023-12-31
0.0134
Worst quarters
2021-09-30
0.000025
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0415
0.0313
0.0208
UBS Select 100% US Treasury Preferred Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0.0018
0
0
0.0001
0.0001
0.0019
0.0019
0.0005
0.0005
0.0014
0.0014
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
14
56
102
238
14
56
102
238
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver/expense reimbursement agreement for the first year only. The fund invests in securities through an underlying master fund, 100% US Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of 100% US Treasury Master Fund, including management fees allocated from 100% US Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, under normal circumstances, the fund invests exclusively in a diversified portfolio of high quality, US Treasury money market instruments and may also hold cash.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. In order to qualify as a “government money market fund” under federal regulations, the fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities); however, as noted above, the fund expects to further limit its investments, and under normal circumstances, the fund invests exclusively in a diversified portfolio of high quality, US Treasury money market instruments and may also hold cash. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states. The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The Fund will generally hold a portion of its assets in cash for operational purposes.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US withholding tax risk:</span> The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. However, there can be no assurance that any or all of the fund’s distributions will be exempt from US withholding tax.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the performance of the fund’s Class T shares has varied over its first calendar year of operations.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s Class T and Class P shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Select 100% US Treasury Preferred Fund Annual Total Returns Total Return of Class T Shares (2025 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.77%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during year shown—3Q 2025: 1.04%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during year shown—4Q 2025: 0.95%</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">1-888-793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0177
Best quarter
2025-09-30
0.0104
Worst quarter
2025-12-31
0.0095
1-888-793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0411
0.0451
0.0411
0.0437
2024-03-13
2024-06-28
UBS Prime Reserves Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0
0.0018
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same<sup style="font-size: 75%; vertical-align: top;">.*</sup></div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
18
58
101
230
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">The fund invests in securities through an underlying master fund, Prime CNAV Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime CNAV Master Fund, including management fees allocated from Prime CNAV Master Fund.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality money market instruments of governmental and private issuers. These may include:</div>
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<tr style="page-break-inside: avoid;">
<td style="width: 1%; vertical-align: top; text-align: left;">•</td>
<td style="width: 1%; vertical-align: top;"> </td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">short-term obligations of the US government and its agencies and instrumentalities;</div> </td> </tr> </table>
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 1%; vertical-align: top; text-align: left;">•</td>
<td style="width: 1%; vertical-align: top;"> </td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">repurchase agreements;</div> </td> </tr> </table>
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<tr style="page-break-inside: avoid;">
<td style="width: 1%; vertical-align: top; text-align: left;">•</td>
<td style="width: 1%; vertical-align: top;"> </td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">obligations of issuers in the financial services group of industries;</div> </td> </tr> </table>
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 1%; vertical-align: top; text-align: left;">•</td>
<td style="width: 1%; vertical-align: top;"> </td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">commercial paper, other corporate obligations and asset-backed securities; and</div> </td> </tr> </table>
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 10pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 1%; vertical-align: top; text-align: left;">•</td>
<td style="width: 1%; vertical-align: top;"> </td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">municipal money market instruments.</div> </td> </tr> </table> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars. The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a “retail money market fund,” as such term is defined in the rule governing money market funds and related interpretations. “Retail money market funds” are money market funds that have policies and procedures reasonably designed to limit all beneficial owners of the fund to natural persons. As a “retail money market fund,” the fund is permitted to seek to maintain a stable price per share.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may be subject to a liquidity fee if the fund’s board believes such fee is in the best interests of the fund.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is classified by UBS AM as an “ESG-integrated” fund. The fund’s investment process integrates material sustainability and/or environmental, social and governance (“ESG”) considerations into the research process for all portfolio investments and portfolio holdings, except repurchase agreements with certain counterparties. <span style="font-weight: bold;"></span>ESG integration is driven by taking into account material sustainability and/or ESG risks which could impact investment returns, rather than being driven by specific ethical principles or norms. The analysis of material sustainability and/or ESG considerations can include many different aspects, including, for example, the carbon footprint, employee health and well-being, supply chain management, fair customer treatment and governance processes of a company. The fund’s portfolio managers may still invest in securities without respect to sustainability and/or ESG considerations or in securities which present sustainability and/or ESG risks, including<span style="font-weight: bold;"></span> where the portfolio managers believe the potential compensation outweighs the risks identified.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
The fund may impose a fee upon the sale of your shares.
An investment in the fund is not a bank account and not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s ability to maintain a $1.00 share price.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Concentration risk:</span> The fund will invest a significant portion of its assets in securities, including asset‑backed securities, issued by companies in the financial services group of industries, including US banks, non-US banks, broker-dealers, insurance companies, and finance companies (e.g., automobile finance). Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Financial services sector risk:</span> Investments of the fund in the financial services sector may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Asset-backed securities risk:</span> The fund may purchase securities representing interests in underlying assets, but structured to provide certain advantages not inherent in those assets (e.g., enhanced liquidity and yields linked to short-term interest rates). If those securities behaved in a way that the advisor did not anticipate, or if the security structures encountered unexpected difficulties, the fund could suffer a loss. Structured securities represent a significant portion of the short-term securities markets.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk: </span>There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk: </span>Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement. Repurchase agreements involving obligations other than US government securities (such as commercial paper, corporate bonds, mortgage loans and equities) may be subject to special risks and may not have the benefit of certain protections in the event of the counterparty’s insolvency. If the seller or guarantor becomes insolvent, the fund may suffer delays, costs and possible losses in connection with the disposition of collateral.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Foreign investing risk:</span> The value of the fund’s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund’s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Municipal securities risk:</span> Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund’s net asset value (“NAV”) and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Prime Reserves Fund Annual Total Returns Total return (2017 was the fund’s first full calendar year)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.80%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.37%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarters during years shown—2Q & 3Q 2021: 0.00% (Actual total returns were 0.0025%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor at UBS Financial Services Inc., (2) by calling 1-888-793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0180
Best quarter
2023-12-31
0.0137
Worst quarter
2021-09-30
0.000025
1-888-793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0423
0.0321
2016-01-19
0.0221
UBS Prime Preferred Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0
0.0018
0.0004
0.0014
2027-08-31
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
14
54
97
226
*Except that the expenses reflect the effects of the fund’s fee waiver agreement for the first year only. The fund invests in securities through an underlying master fund, Prime CNAV Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime CNAV Master Fund, including management fees allocated from Prime CNAV Master Fund.
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. The fund seeks to achieve its objective by investing in a diversified portfolio of high quality money market instruments of governmental and private issuers. These may include:</div>
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<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">short-term obligations of the US government and its agencies and instrumentalities;</div> </td> </tr> </table>
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<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">repurchase agreements;</div> </td> </tr> </table>
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<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">obligations of issuers in the financial services group of industries;</div> </td> </tr> </table>
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<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">commercial paper, other corporate obligations and asset-backed securities; and</div> </td> </tr> </table>
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<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-family: arial; font-size: 10pt; text-align: left;">municipal money market instruments.</div> </td> </tr> </table> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund invests in foreign money market instruments only if they are denominated in US dollars. The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a “retail money market fund,” as such term is defined in the rule governing money market funds and related interpretations. “Retail money market funds” are money market funds that have policies and procedures reasonably designed to limit all beneficial owners of the fund to natural persons. As a “retail money market fund,” the fund is permitted to seek to maintain a stable price per share.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may be subject to a liquidity fee if the fund’s board believes such fee is in the best interests of the fund.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is classified by UBS AM as an “ESG-integrated” fund. The fund’s investment process integrates material sustainability and/or environmental, social and governance (“ESG”) considerations into the research process for all portfolio investments and portfolio holdings, except repurchase agreements with certain counterparties. ESG integration is driven by taking into account material sustainability and/or ESG risks which could impact investment returns, rather than being driven by specific ethical principles or norms. The analysis of material sustainability and/or ESG considerations can include many different aspects, including, for example, the carbon footprint, employee health and well-being, supply chain management, fair customer treatment and governance processes of a company. The fund’s portfolio managers may still invest in securities without respect to sustainability and/or ESG considerations or in securities which present sustainability and/or ESG risks, including where the portfolio managers believe the potential compensation outweighs the risks identified.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions. UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
The fund may impose a fee upon the sale of your shares.
An investment in the fund is not a bank account and not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk</span><span style="font-weight: bold;">:</span> Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk</span><span style="font-weight: bold;">:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s ability to maintain a $1.00 share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s ability to maintain a $1.00 share price.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Concentration risk</span><span style="font-weight: bold;">:</span> The fund will invest a significant portion of its assets in securities, including asset-backed securities, issued by companies in the financial services group of industries, including US banks, non-US banks, broker-dealers, insurance companies, and finance companies (e.g., automobile finance). Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Financial services sector risk:</span> Investments of the fund in the financial services sector may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Asset-backed securities risk</span><span style="font-weight: bold;">:</span> The fund may purchase securities representing interests in underlying assets, but structured to provide certain advantages not inherent in those assets (e.g., enhanced liquidity and yields linked to short-term interest rates). If those securities behaved in a way that the advisor did not anticipate, or if the security structures encountered unexpected difficulties, the fund could suffer a loss. Structured securities represent a significant portion of the short-term securities markets.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk: </span>There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk:</span> Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement. Repurchase agreements involving obligations other than US government securities (such as commercial paper, corporate bonds, mortgage loans and equities) may be subject to special risks and may not have the benefit of certain protections in the event of the counterparty’s insolvency. If the seller or guarantor becomes insolvent, the fund may suffer delays, costs and possible losses in connection with the disposition of collateral.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Foreign investing risk</span><span style="font-weight: bold;">:</span> The value of the fund’s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because the fund’s foreign investments must be denominated in US dollars, it generally is not subject to the risk of changes in currency valuations.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Municipal securities risk:</span> Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund’s net asset value and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the fund’s performance has varied from year to year.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Prime Preferred Fund Annual Total Returns Total return (2017 was the fund’s first full calendar year)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.82%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—4Q 2023: 1.38%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during years shown—3Q 2021: 0.00% (Actual total return was 0.0034%)</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0182
Best quarter
2023-12-31
0.0138
Worst quarter
2021-09-30
0.000034
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns (for the periods ended December 31, 2025)
0.0427
0.0325
2016-01-19
0.0225
UBS Ultra Short Income Fund Summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">To provide current income while seeking to maintain low volatility of principal.</div>
Fees and expenses
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. In addition to the fees and expenses described below, you may also be required to pay commissions or other fees to your broker for transactions in Class P shares. Shares of the fund are available in classes other than Class P that have different fees and expenses.</div>
Shareholder fees (fees paid directly from your investment)
0
0
0
0
0
0
Shares of the fund acquired through the exchange of shares of another Family Fund (“Family Funds” include PACE<sup style="font-size: 75%; vertical-align: top;">®</sup> Select funds, series of The UBS Funds and other funds for which UBS Asset Management (US) Inc. serves as principal underwriter) may be subject to a deferred sales charge if you later sell the fund shares acquired in the exchange, based on the terms of the shares of the Family Fund you originally held.
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
0.0020
0.0020
0.0010
0
0.0025
0.0024
0.0055
0.0044
0.0020
0.0019
0.0035
0.0025
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods unless otherwise stated. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
36
156
287
670
26
122
227
536
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver/expense reimbursement agreement for the first year only.</div> </td> </tr> </table>
Portfolio turnover
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund pays transaction costs, such as commissions or dealer spreads, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During the fiscal year ended April 30, 2026, the fund’s portfolio turnover rate was 56% of the average value of its portfolio.</div>
0.56
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Under normal circumstances, the fund invests in fixed income securities and money market instruments. The fund’s investments in securities may include, but are not limited to, government obligations including agencies, debt issued by government-sponsored and supranational entities, as well as municipal securities, corporate debt, mortgage-backed, asset-backed, and inflation-linked securities. Investments in money market instruments may include, but are not limited to, commercial paper (including asset-backed commercial paper), certificates of deposit, notes, time deposits, repurchase agreements and other money market securities. The fund may invest in money market funds, including those advised by UBS Asset Management (Americas) LLC (“UBS AM”), the fund’s investment advisor.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest in securities of any maturity, but will generally limit its weighted average portfolio duration to one year or less.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund normally invests in investment grade securities. Investment grade securities possess a minimum rating of Baa3 by Moody’s Investors Service, Inc. (“Moody’s”) or BBB‑ by Standard & Poor’s Financial Services LLC (“S&P”) or Fitch Ratings, Inc. (“Fitch”) for long-term ratings and/or equivalent short-term ratings, comparably rated by another nationally recognized statistical rating organization, or, if unrated, are determined by UBS AM to be of comparable quality. The fund may at times hold securities rated below‑investment‑grade if the rating for a security held by the fund is subsequently reduced to below-investment-grade (commonly referred to as “junk bonds,” which are considered speculative in nature).</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s investments may have all types of interest rate payment and reset terms, including floating or variable rate, zero coupon and other features. In addition, the fixed income securities purchased by the fund may be of US and non‑US issuers. The fund’s investments are typically denominated in US dollars or hedged to US dollars.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is not a money market fund and does not seek to maintain a stable net asset value (“NAV”) per share. The fund should not be considered to be a money market fund or the equivalent of a money market fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM acts as the investment advisor to the fund, and makes the fund’s investment decisions. UBS AM selects investments for the fund based on a rigorous valuation and research framework, combining top‑down macroeconomic and quantitative research with issuer level credit analysis. This dynamic approach allows UBS AM to exploit diversified sources of return, which UBS AM believes is key to delivering consistent performance over time.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The top‑down process involves formulation of broad investment views and views regarding macroeconomic trends. UBS AM’s views on the direction of interest rates, yield curve shape, sectors, and volatility help formulate final portfolio positioning.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">After UBS AM establishes the top‑down strategy, the portfolio management team, working closely with UBS AM’s research analysts, builds portfolios that combines top‑down allocation targets with bottom‑up security specific strategies. Research is a fundamental component of UBS AM’s globally integrated investment platform and consists of top‑down macroeconomic analysis as well as bottom‑up sector and issuer level research. UBS AM uses rigorous credit/structure analysis and relative pricing to choose securities that it believes have superior risk/return characteristics. The ultimate goal of any purchase decision is to be compensated for a given level of risk. Prudent diversification seeks to ensure an appropriate risk/return relationship. Security selection represents the final level of decision-making in our investment process. UBS AM selects individual securities that it believes will give the portfolio the desired exposures with optimal relative value. UBS AM integrates risk management throughout the investment process.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield. The fund may sell investments that UBS AM believes are no longer favorable with regard to these factors or for other reasons.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is classified by UBS AM as an “ESG-integrated” fund. The fund’s investment process integrates material sustainability and/or environmental, social and governance (“ESG”) considerations into the research process for all portfolio investments and portfolio holdings, except repurchase agreements with certain counterparties and except asset-backed and mortgage-backed securities. ESG integration is driven</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">by taking into account material sustainability and/or ESG risks which could impact investment returns, rather than being driven by specific ethical principles or norms. The analysis of material sustainability and/or ESG considerations can include many different aspects, including, for example, the carbon footprint, employee health and well-being, supply chain management, fair customer treatment and governance processes of a company. The fund’s portfolio managers may still invest in securities without respect to sustainability and/or ESG considerations or in securities which present sustainability and/or ESG risks, including where the portfolio managers believe the potential compensation outweighs the risks identified.</div>
The prices for the fund’s shares will fluctuate, and you may lose money by investing in the fund.
An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk: </span>The risk that the fund could lose money if the issuer or guarantor of a fixed income security or financial institutions that have entered into repurchase agreements with the fund are unable or unwilling to meet their financial obligations or complete transactions. This risk is likely greater for lower quality investments than for investments that are higher quality.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Financial services sector risk: </span>Investments of the fund in the financial services group of industries or sectors may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Concentration risk: </span>The fund will invest a significant portion of its assets in securities, including asset-backed securities, issued by companies in the financial services group of industries or sectors, including US banks, non-US banks, broker-dealers, insurance companies, and finance companies (<span style="font-style: italic;">e.g.</span>, automobile finance). Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk: </span>An increase in prevailing interest rates typically causes the value of fixed income securities to fall, and the fund’s yield will tend to lag behind prevailing rates. Changes in interest rates will likely affect the value of longer-duration fixed income securities more than shorter-duration securities and higher quality securities more than lower quality securities. When interest rates are falling, some fixed income securities provide that the issuer may repay them earlier than the maturity date, and if this occurs the fund may have to reinvest these repayments at lower interest rates. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk: </span>Certain of the fund’s investments may present liquidity risk. Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk: </span>The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with a similar benchmark or similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk: </span>The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the stock and bond markets fluctuate. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Mortgage- and asset-backed securities risk: </span>The fund may invest in mortgage- and asset-backed securities that are subject to prepayment or call risk, which is the risk that the borrower’s payments may be received earlier or later than expected due to changes in prepayment rates on underlying loans. Faster prepayments often happen when interest rates are falling. As a result, the fund may reinvest these early payments at lower interest rates, thereby reducing the fund’s income. Conversely, when interest rates rise, prepayments may happen more slowly, causing the security to lengthen in duration. Longer duration securities tend to be more volatile. Securities may be prepaid at a price less than the original purchase value. An unexpectedly high rate of defaults on the mortgages held by a mortgage pool may adversely affect the value of mortgage-backed securities and could result in losses to the fund.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Floating or variable rate securities risk: </span>Floating or variable rate securities bear interest at rates that are not fixed but that vary with changes in specified market rates or indices. The market value of floating rate and variable rate securities generally fluctuates less than the market value of fixed rate obligations. Accordingly, as interest rates decrease or increase, the potential for capital appreciation or capital depreciation is less than for fixed rate obligations. Additionally, these securities may decline in value if their coupon/interest rates do not reset as high, or as quickly, as comparable market interest rates, and generally carry lower yields than fixed rate securities of the same maturity.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">NAV risk: </span>The fund is not a money market fund, does not attempt to maintain a stable NAV per share, and is not subject to the rules that govern the quality, maturity, liquidity and other features of securities that money market funds may purchase. Under normal conditions, the fund’s investments are likely to be more susceptible than a money market fund’s investments to interest rate risk, valuation risk, credit risk, and other risks relevant to the fund’s investments. The fund’s NAV per share will fluctuate. Because the fund is not a money market fund, it does not qualify for the special money market fund tax treatment or tax accounting methods under US Treasury regulations.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Prepayment risk: </span>Payments on bonds and other fixed income securities that are backed by mortgage loans or similar assets may be prepaid more rapidly than expected, especially when interest rates are falling, and the fund may have to reinvest those prepayments at lower interest rates. When interest rates are rising, slower prepayments may extend the duration of the securities and may reduce their value.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Valuation risk: </span>During periods of reduced market liquidity or in the absence of readily available market quotations for investments, the ability of the fund to value the fund’s investments becomes more difficult</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">and the judgment of the fund’s investment advisor may play a greater role in the valuation of the investments due to reduced availability of reliable objective pricing data.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Municipal securities risk: </span>Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund’s NAV and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Zero coupon securities risk: </span>Zero coupon securities are securities on which no periodic interest payments are made but instead are sold at a deep discount from their face value. Zero coupon securities are generally more sensitive to changes in interest rates than debt obligations of comparable maturities that make current interest payments. This means that when interest rates fall, the value of zero coupon securities generally rises more rapidly than securities paying interest on a current basis. However, when interest rates rise, their value generally falls more dramatically.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US government securities risk: </span>There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk: </span>Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement. Repurchase agreements involving obligations other than US government securities (such as commercial paper, corporate bonds, mortgage loans and equities) may be subject to special risks and may not have the benefit of certain protections in the event of the counterparty’s insolvency. If the seller or guarantor becomes insolvent, the fund may suffer delays, costs and possible losses in connection with the disposition of collateral.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Investments in money market funds risk: </span>Certain money market funds may seek to maintain a stable $1 NAV per share (“stable NAV money market funds”) or have a share price that fluctuates (“variable NAV money market funds”). Although a stable NAV money market fund seeks to maintain a stable $1 NAV per share, it is possible to lose money by investing in such a money market fund. Because the NAV of a variable NAV money market fund will fluctuate, when the fund sells the shares it owns they may be worth more or less than what the fund originally paid for them. In addition, neither type of money market fund is designed to offer capital appreciation. Certain money market funds may impose a fee upon the sale of shares.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Sovereign debt risk: </span>Sovereign debt includes bonds that are issued by foreign governments or their agencies, instrumentalities or political subdivisions or by foreign central banks. Sovereign debt also may be</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">issued by quasi-governmental entities that are owned by foreign governments but are not backed by their full faith and credit or general taxing powers. Investment in sovereign debt involves special risks. The issuer of the debt or the governmental authorities that control the repayment of the debt may be unable or unwilling to repay principal and/or interest when due in accordance with the terms of such debt, and the fund may have limited legal recourse in the event of a default.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Foreign investing risk: </span>The value of the fund’s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because, under normal circumstances, the fund’s foreign investments are typically denominated in US dollars or hedged to US dollars, it generally is not subject to the risk of changes in currency valuations.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Derivatives risk: </span>The value of derivatives—so called because their value derives from the value of an underlying asset, reference rate or index—may rise or fall more rapidly than other investments. It is possible for the fund to lose more than the amount it invested in the derivative. When using derivatives for hedging purposes, the fund’s overall returns may be reduced if the hedged investment experiences a favorable price movement. In addition, if the fund has insufficient cash to meet daily variation margin or payment requirements, it may have to sell securities from its portfolio at a time when it may be disadvantageous to do so. The risks of investing in derivative instruments also include market and management risks. Derivatives relating to fixed income markets are especially susceptible to interest rate risk and credit risk. In addition, many types of swaps and other derivatives may be subject to liquidity risk, counterparty risk, credit risk and mispricing or valuation complexity. Derivatives also involve the risk that changes in the value of a derivative may not correlate as anticipated with the underlying asset, rate, index or overall securities markets, thereby reducing their effectiveness. These derivatives risks are different from, and may be greater than, the risks associated with investing directly in securities and other instruments. Regulation relating to a mutual fund’s use of derivatives and related instruments, including Rule 18f-4 under the Investment Company Act of 1940, as amended (the “1940 Act”), (“Rule 18f-4”), could potentially limit or impact the fund’s ability to invest in derivatives, limit the fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the fund’s performance.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The performance information that follows shows the fund’s performance information in a bar chart and an average annual total returns table. The information provides some indication of the risks of investing in the fund by showing changes in the fund’s performance from year to year and by showing how the fund’s average annual total returns compare with those of the Bloomberg US Aggregate Bond Index, which represents a broad measure of market performance, over time. The table also includes the average annual returns of the ICE BofA 3-Month Treasury Bill Index, which is generally representative of the market sectors or types of investments in which the fund invests. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Updated performance for the fund is available at https://www.ubs.com/us/en/assetmanagement/funds/mutual-fund-performance.html.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. In addition, the after-tax returns shown are not relevant to investors who hold fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts. After-tax returns for other classes will vary from the Class A shares’ after-tax returns shown.</div>
The information provides some indication of the risks of investing in the fund by showing changes in the fund’s performance from year to year and by showing how the fund’s average annual total returns compare with those of the Bloomberg US Aggregate Bond Index, which represents a broad measure of market performance, over time.
The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.
https://www.ubs.com/us/en/assetmanagement/funds/mutual-fund-performance.html
After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. In addition, the after-tax returns shown are not relevant to investors who hold fund shares through tax-advantaged arrangements, such as 401(k) plans or individual retirement accounts.
After-tax returns for other classes will vary from the Class A shares’ after-tax returns shown.
UBS Ultra Short Income Fund Annual Total Returns of Class A Shares (2019 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.75%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—2Q 2020: 1.70%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during years shown—1Q 2020: (1.06)%</div>
Total return
2026-06-30
0.0175
Best quarter
2020-06-30
0.0170
Worst quarter
2020-03-31
-0.0106
Average annual total returns (for the periods ended December 31, 2025)
0.0453
0.0299
0.0258
0.0266
0.0164
0.0144
0.0266
0.0170
0.0149
0.0463
0.0309
0.0267
0.0730
-0.0036
0.0199
0.0421
0.0319
0.0265
2018-05-29
2018-05-29
2018-05-29
2018-05-29
UBS Ultra Short Income Fund Summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">To provide current income while seeking to maintain low volatility of principal.</div>
Fees and expenses
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
0.0020
0
0.0024
0.0044
0.0021
0.0023
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods unless otherwise stated. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
24
120
225
534
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver/expense reimbursement agreement for the first year only.</div> </td> </tr> </table>
Portfolio turnover
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund pays transaction costs, such as commissions or dealer spreads, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During the fiscal year ended April 30, 2026, the fund’s portfolio turnover rate was 56% of the average value of its portfolio.</div>
0.56
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Under normal circumstances, the fund invests in fixed income securities and money market instruments. The fund’s investments in securities may include, but are not limited to, government obligations including agencies, debt issued by government-sponsored and supranational entities, as well as municipal securities, corporate debt, mortgage-backed, asset-backed, and inflation-linked securities. Investments in money market instruments may include, but are not limited to, commercial paper (including asset-backed commercial paper), certificates of deposit, notes, time deposits, repurchase agreements and other money market securities. The fund may invest in money market funds, including those advised by UBS Asset Management (Americas) LLC (“UBS AM”), the fund’s investment advisor.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest in securities of any maturity, but will generally limit its weighted average portfolio duration to one year or less.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund normally invests in investment grade securities. Investment grade securities possess a minimum rating of Baa3 by Moody’s Investors Service, Inc. (“Moody’s”) or BBB‑ by Standard & Poor’s Financial Services LLC (“S&P”) or Fitch Ratings, Inc. (“Fitch”) for long-term ratings and/or equivalent short-term ratings, comparably rated by another nationally recognized statistical rating organization, or, if unrated, are determined by UBS AM to be of comparable quality. The fund may at times hold securities rated below-investment-grade if the rating for a security held by the fund is subsequently reduced to below-investment-grade (commonly referred to as “junk bonds,” which are considered speculative in nature).</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s investments may have all types of interest rate payment and reset terms, including floating or variable rate, zero coupon and other features. In addition, the fixed income securities purchased by the fund may be of US and non‑US issuers. The fund’s investments are typically denominated in US dollars or hedged to US dollars.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund will, under normal circumstances, invest more than 25% of its total assets in the financial services group of industries.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is not a money market fund and does not seek to maintain a stable net asset value (“NAV”) per share. The fund should not be considered to be a money market fund or the equivalent of a money market fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM acts as the investment advisor to the fund, and makes the fund’s investment decisions. UBS AM selects investments for the fund based on a rigorous valuation and research framework, combining top‑down macroeconomic and quantitative research with issuer level credit analysis. This dynamic approach allows UBS AM to exploit diversified sources of return, which UBS AM believes is key to delivering consistent performance over time.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The top‑down process involves formulation of broad investment views and views regarding macroeconomic trends. UBS AM’s views on the direction of interest rates, yield curve shape, sectors, and volatility help formulate final portfolio positioning.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">After UBS AM establishes the top‑down strategy, the portfolio management team, working closely with UBS AM’s research analysts, builds portfolios that combines top‑down allocation targets with bottom‑up security specific strategies. Research is a fundamental component of UBS AM’s globally integrated investment platform and consists of top‑down macroeconomic analysis as well as bottom‑up sector and issuer level research. UBS AM uses rigorous credit/structure analysis and relative pricing to choose securities that it believes have superior risk/return characteristics. The ultimate goal of any purchase decision is to be compensated for a given level of risk. Prudent diversification seeks to ensure an appropriate risk/return relationship. Security selection represents the final level of decision-making in our investment process. UBS AM selects individual securities that it believes will give the portfolio the desired exposures with optimal relative value. UBS AM integrates risk management throughout the investment process.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield. The fund may sell investments that UBS AM believes are no longer favorable with regard to these factors or for other reasons.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is classified by UBS AM as an “ESG-integrated” fund. The fund’s investment process integrates material sustainability and/or environmental, social and governance (“ESG”) considerations into the research process for all portfolio investments and portfolio holdings, except repurchase agreements with</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">certain counterparties and except asset-backed and mortgage-backed securities. ESG integration is driven by taking into account material sustainability and/or ESG risks which could impact investment returns, rather than being driven by specific ethical principles or norms. The analysis of material sustainability and/or ESG considerations can include many different aspects, including, for example, the carbon footprint, employee health and well-being, supply chain management, fair customer treatment and governance processes of a company. The fund’s portfolio managers may still invest in securities without respect to sustainability and/or ESG considerations or in securities which present sustainability and/or ESG risks, including where the portfolio managers believe the potential compensation outweighs the risks identified.</div>
The prices for the fund’s shares will fluctuate, and you may lose money by investing in the fund.
An investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk: </span>The risk that the fund could lose money if the issuer or guarantor of a fixed income security or financial institutions that have entered into repurchase agreements with the fund are unable or unwilling to meet their financial obligations or complete transactions. This risk is likely greater for lower quality investments than for investments that are higher quality.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Financial services sector risk: </span>Investments of the fund in the financial services group of industries or sectors may be particularly affected by economic cycles, business developments, interest rate changes and regulatory changes.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Concentration risk: </span>The fund will invest a significant portion of its assets in securities, including asset-backed securities, issued by companies in the financial services group of industries or sectors, including US banks, non-US banks, broker-dealers, insurance companies, and finance companies (<span style="font-style: italic;">e.g.</span>, automobile finance). Accordingly, the fund will be more susceptible to developments that affect those industries than other funds that do not concentrate their investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk: </span>An increase in prevailing interest rates typically causes the value of fixed income securities to fall, and the fund’s yield will tend to lag behind prevailing rates. Changes in interest rates will likely affect the value of longer-duration fixed income securities more than shorter-duration securities and higher quality securities more than lower quality securities. When interest rates are falling, some fixed income securities provide that the issuer may repay them earlier than the maturity date, and if this occurs the fund may have to reinvest these repayments at lower interest rates. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk: </span>Certain of the fund’s investments may present liquidity risk. Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk: </span>The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with a similar benchmark or similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk: </span>The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the stock and bond markets fluctuate. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Mortgage- and asset-backed securities risk: </span>The fund may invest in mortgage- and asset-backed securities that are subject to prepayment or call risk, which is the risk that the borrower’s payments may be received earlier or later than expected due to changes in prepayment rates on underlying loans. Faster prepayments often happen when interest rates are falling. As a result, the fund may reinvest these early payments at lower interest rates, thereby reducing the fund’s income. Conversely, when interest rates rise, prepayments may happen more slowly, causing the security to lengthen in duration. Longer duration securities tend to be more volatile. Securities may be prepaid at a price less than the original purchase value. An unexpectedly high rate of defaults on the mortgages held by a mortgage pool may adversely affect the value of mortgage-backed securities and could result in losses to the fund.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Floating or variable rate securities risk: </span>Floating or variable rate securities bear interest at rates that are not fixed but that vary with changes in specified market rates or indices. The market value of floating rate and variable rate securities generally fluctuates less than the market value of fixed rate obligations. Accordingly, as interest rates decrease or increase, the potential for capital appreciation or capital depreciation is less than for fixed rate obligations. Additionally, these securities may decline in value if their coupon/interest rates do not reset as high, or as quickly, as comparable market interest rates, and generally carry lower yields than fixed rate securities of the same maturity.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">NAV risk: </span>The fund is not a money market fund, does not attempt to maintain a stable NAV per share, and is not subject to the rules that govern the quality, maturity, liquidity and other features of securities that money market funds may purchase. Under normal conditions, the fund’s investments are likely to be more susceptible than a money market fund’s investments to interest rate risk, valuation risk, credit risk, and other risks relevant to the fund’s investments. The fund’s NAV per share will fluctuate. Because the fund is not a money market fund, it does not qualify for the special money market fund tax treatment or tax accounting methods under US Treasury regulations.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Prepayment risk: </span>Payments on bonds and other fixed income securities that are backed by mortgage loans or similar assets may be prepaid more rapidly than expected, especially when interest rates are</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">falling, and the fund may have to reinvest those prepayments at lower interest rates. When interest rates are rising, slower prepayments may extend the duration of the securities and may reduce their value.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Valuation risk: </span>During periods of reduced market liquidity or in the absence of readily available market quotations for investments, the ability of the fund to value the fund’s investments becomes more difficult and the judgment of the fund’s investment advisor may play a greater role in the valuation of the investments due to reduced availability of reliable objective pricing data.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Municipal securities risk: </span>Municipal securities are subject to interest rate and credit risks. The ability of a municipal issuer to make payments and the value of municipal securities can be affected by uncertainties in the municipal securities market. Such uncertainties could cause increased volatility in the municipal securities market and could negatively impact the fund’s NAV and/or the distributions paid by the fund. Municipalities continue to experience difficulties in the current economic and political environment.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Zero coupon securities risk: </span>Zero coupon securities are securities on which no periodic interest payments are made but instead are sold at a deep discount from their face value. Zero coupon securities are generally more sensitive to changes in interest rates than debt obligations of comparable maturities that make current interest payments. This means that when interest rates fall, the value of zero coupon securities generally rises more rapidly than securities paying interest on a current basis. However, when interest rates rise, their value generally falls more dramatically.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US government securities risk: </span>There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk: </span>Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement. Repurchase agreements involving obligations other than US government securities (such as commercial paper, corporate bonds, mortgage loans and equities) may be subject to special risks and may not have the benefit of certain protections in the event of the counterparty’s insolvency. If the seller or guarantor becomes insolvent, the fund may suffer delays, costs and possible losses in connection with the disposition of collateral.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Investments in money market funds risk: </span>Certain money market funds may seek to maintain a stable $1 NAV per share (“stable NAV money market funds”) or have a share price that fluctuates (“variable NAV money market funds”). Although a stable NAV money market fund seeks to maintain a stable $1 NAV per share, it is possible to lose money by investing in such a money market fund. Because the NAV of a variable NAV money market fund will fluctuate, when the fund sells the shares it owns they may be worth more or</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">less than what the fund originally paid for them. In addition, neither type of money market fund is designed to offer capital appreciation. Certain money market funds may impose a fee upon the sale of shares.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Sovereign debt risk: </span>Sovereign debt includes bonds that are issued by foreign governments or their agencies, instrumentalities or political subdivisions or by foreign central banks. Sovereign debt also may be issued by quasi-governmental entities that are owned by foreign governments but are not backed by their full faith and credit or general taxing powers. Investment in sovereign debt involves special risks. The issuer of the debt or the governmental authorities that control the repayment of the debt may be unable or unwilling to repay principal and/or interest when due in accordance with the terms of such debt, and the fund may have limited legal recourse in the event of a default.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Foreign investing risk: </span>The value of the fund’s investments in foreign securities may fall due to adverse political, social and economic developments abroad. However, because, under normal circumstances, the fund’s foreign investments are typically denominated in US dollars or hedged to US dollars, it generally is not subject to the risk of changes in currency valuations.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Derivatives risk: </span>The value of derivatives—so called because their value derives from the value of an underlying asset, reference rate or index—may rise or fall more rapidly than other investments. It is possible for the fund to lose more than the amount it invested in the derivative. When using derivatives for hedging purposes, the fund’s overall returns may be reduced if the hedged investment experiences a favorable price movement. In addition, if the fund has insufficient cash to meet daily variation margin or payment requirements, it may have to sell securities from its portfolio at a time when it may be disadvantageous to do so. The risks of investing in derivative instruments also include market and management risks. Derivatives relating to fixed income markets are especially susceptible to interest rate risk and credit risk. In addition, many types of swaps and other derivatives may be subject to liquidity risk, counterparty risk, credit risk and mispricing or valuation complexity. Derivatives also involve the risk that changes in the value of a derivative may not correlate as anticipated with the underlying asset, rate, index or overall securities markets, thereby reducing their effectiveness. These derivatives risks are different from, and may be greater than, the risks associated with investing directly in securities and other instruments. Regulation relating to a mutual fund’s use of derivatives and related instruments, including Rule 18f-4 under the Investment Company Act of 1940, as amended (the “1940 Act”), (“Rule 18f-4”), could potentially limit or impact the fund’s ability to invest in derivatives, limit the fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the fund’s performance.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The performance information that follows shows the fund’s performance information in a bar chart and an average annual total returns table. The information provides some indication of the risks of investing in the fund by showing changes in the fund’s performance from year to year and by showing how the fund’s average annual total returns compare with those of the Bloomberg US Aggregate Bond Index, which represents a broad measure of market performance, over time. The table also includes the average annual returns of</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">the ICE BofA 3-Month Treasury Bill Index, which is generally representative of the market sectors or types of investments in which the fund invests. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. Updated performance for the fund is available at https://www.ubs.com/us/en/assetmanagement/funds/mutual-fund-performance.html.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">After‑tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after‑tax returns depend on an investor’s tax situation and may differ from those shown. In addition, the after‑tax returns shown are not relevant to investors who hold fund shares through tax‑advantaged arrangements, such as 401(k) plans or individual retirement accounts. After‑tax returns for other classes will vary from the Class I shares’ after‑tax returns shown.</div>
The information provides some indication of the risks of investing in the fund by showing changes in the fund’s performance from year to year and by showing how the fund’s average annual total returns compare with those of the Bloomberg US Aggregate Bond Index, which represents a broad measure of market performance, over time.
The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future.
https://www.ubs.com/us/en/assetmanagement/funds/mutual-fund-performance.html
After‑tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Actual after‑tax returns depend on an investor’s tax situation and may differ from those shown. In addition, the after‑tax returns shown are not relevant to investors who hold fund shares through tax‑advantaged arrangements, such as 401(k) plans or individual retirement accounts.
After‑tax returns for other classes will vary from the Class I shares’ after‑tax returns shown.
UBS Ultra Short Income Fund Annual Total Returns of Class I Shares (2019 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.81%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during years shown—2Q 2020: 1.74%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during years shown—1Q 2020: (1.14)%</div>
Total return
2026-06-30
0.0181
Best quarter
2020-06-30
0.0174
Worst quarter
2020-03-31
-0.0114
Average annual total returns (for the periods ended December 31, 2025)
0.0465
0.0309
0.0266
0.0273
0.0169
0.0148
0.0273
0.0176
0.0153
0.0730
-0.0036
0.0199
0.0421
0.0319
0.0265
2018-05-29
2018-05-29
2018-05-29
Cantor Fitzgerald Government Money Market Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0.0018
0
0
0.0030
0.0005
0.0025
0.0000
0.0005
0.0005
0.0048
0.0023
0.0018
0.0005
0.0030
0.0018
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
31
136
251
586
18
69
124
288
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver/expense reimbursement agreement for the first year only. The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, the fund invests in a diversified portfolio of high quality, US government money market instruments and in related repurchase agreements.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. The fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities) in order to qualify as a “government money market fund” under federal regulations. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some states. The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements. US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the US</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">government, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
In addition, under normal circumstances, the fund invests at least 80% of its net assets in US government securities, including government securities subject to repurchase agreements.
US government securities include direct obligations of the US Treasury (such as Treasury bills, notes or bonds) and obligations issued or guaranteed as to principal and interest (but not as to market value) by the USgovernment, its agencies or its instrumentalities. Government securities subject to repurchase agreements include repurchase agreements that are collateralized fully by government securities.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund may invest a significant percentage (50% or more) of its assets in repurchase agreements. Repurchase agreements are transactions in which the fund purchases government securities and simultaneously commits to resell them to the same counterparty at a future time and at a price reflecting a market rate of interest. Income from repurchase agreements may not be exempt from state and local income taxation. Repurchase agreements may offer a higher yield than investments directly in government securities. In deciding whether an investment in a repurchase agreement is more attractive than a direct investment in government securities, the fund considers the possible loss of this tax advantage.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The fund’s sponsor is not required to reimburse the fund for losses, and you should not expect that the sponsor will provide financial support to the fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments or financial institutions that have entered into repurchase agreements with the fund may fail to make payments when due or complete transactions, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. For example, a US government-sponsored entity, such as Federal National Mortgage Association (“Fannie Mae”) or Federal Home Loan Mortgage Corporation (“Freddie Mac”), although chartered or sponsored by an Act of Congress, may issue securities that are neither insured nor guaranteed by the US Treasury and are therefore riskier than those that are. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Repurchase agreements risk:</span> Repurchase agreements carry certain risks not associated with direct investments in securities, including a possible decline in the market value of the underlying obligations and the risk that the counterparty does not meet its obligations under the agreement.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US withholding tax risk:</span> The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. However, there can be no assurance that any or all of the fund’s distributions will be exempt from US withholding tax.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The bar chart shows how the performance of the fund’s Institutional Shares has varied over its first calendar year of operations.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The table that follows the bar chart shows the average annual returns over various time periods for the fund’s Institutional Shares and Investor Shares.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The following bar chart and table provide information about the fund’s performance and thus give some indication of the risks of an investment in the fund.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
Cantor Fitzgerald Government Money Market Fund Annual Total Returns Total Return of Institutional Shares (2025 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.76%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during year shown—3Q 2025: 1.04%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during year shown—4Q 2025: 0.96%</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.cantormmf.com.</div>
Total return
2026-06-30
0.0176
Best quarter
2025-09-30
0.0104
Worst quarter
2025-12-31
0.0096
1‑888‑793 8637
https://www.cantormmf.com
Average annual total returns (for the periods ended December 31, 2025)
0.0411
0.0450
0.0399
0.0437
2024-03-25
2024-01-16
UBS Select 100% US Treasury Institutional Fund Fund summary
Investment objective
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Maximum current income consistent with liquidity and the preservation of capital.</div>
Fees and expenses of the fund
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">These tables describe the fees and expenses that you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as fees to financial intermediaries, which are not reflected in the table or example below.</div>
Shareholder fees (fees paid directly from your investment)
0
0
Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)*
0.0018
0
0.0001
0.0019
0.0001
0.0018
The Fund’s “Other Expenses” have been estimated to reflect expenses to be incurred during the first fiscal year.
August 31, 2027
Example
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund’s operating expenses remain the same.*</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Although your actual costs may be higher or lower, based on these assumptions your costs would be:</div>
18
60
106
242
<table cellpadding="0" cellspacing="0" style="border-collapse: collapse; font-family: arial narrow; font-size: 8pt; border-spacing: 0px; width: 100%;">
<tr style="page-break-inside: avoid;">
<td style="width: 2%; vertical-align: top; text-align: left;">*</td>
<td style="vertical-align: top; text-align: left;"> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 8pt; font-family: arial narrow; text-align: left;">Except that the expenses reflect the effects of the fund’s fee waiver/expense reimbursement agreement for the first year only. The fund invests in securities through an underlying master fund, 100% US Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of 100% US Treasury Master Fund, including management fees allocated from 100% US Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.</div> </td> </tr> </table>
Principal strategies Principal investments
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund is a money market fund and seeks to maintain a stable price of $1.00 per share. To do this, under normal circumstances, the fund invests exclusively in a diversified portfolio of high quality, US Treasury money market instruments and may also hold cash.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Money market instruments generally are short-term debt obligations. They also may include longer-term bonds that have variable interest rates or other special features (e.g., a put option) that give them the financial characteristics of short-term debt. In order to qualify as a “government money market fund” under federal regulations, the fund has adopted a policy to invest 99.5% or more of its total assets in cash, government securities, and/or repurchase agreements that are collateralized fully (<span style="font-style: italic;">i.e.</span>, collateralized by cash and/or government securities); however, as noted above, the fund expects to further limit its investments, and under normal circumstances, the fund invests exclusively in a diversified portfolio of high quality, US Treasury money market instruments and may also hold cash. US Treasury money market instruments include Treasury bills, notes, and floating rate notes. Many US government money market instruments, including those in which the fund invests, pay income that is generally exempt from state and local income tax, although they may be subject to corporate franchise tax in some state. The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The Fund will generally hold a portion of its assets in cash for operational purposes.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The fund invests in securities through an underlying master fund. The fund and its corresponding master fund have the same objective. Unless otherwise indicated, references to the fund include the master fund.</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial; font-weight: bold;">Management process</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS Asset Management (Americas) LLC (“UBS AM”) acts as the investment advisor. As investment advisor, UBS AM makes the fund’s investment decisions. UBS AM selects money market instruments for the fund based on its assessment of relative values and changes in market and economic conditions.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">UBS AM considers safety of principal and liquidity in selecting securities for the fund and thus may not buy securities that pay the highest yield.</div>
You could lose money by investing in the fund.
Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so.
An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
The Fund’s sponsor is not required to reimburse the Fund for losses, and you should not expect that the sponsor will provide financial support to the Fund at any time, including during periods of market stress.
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Credit risk:</span> Issuers of money market instruments may fail to make payments when due, or they may become less willing or less able to do so.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Interest rate risk:</span> The value of the fund’s investments generally will fall when short-term interest rates rise, and its yield will tend to lag behind prevailing rates. Securities with longer maturities generally are subject to greater fluctuations in value. Changes in interest rates will likely affect the value of higher-quality securities more than lower-quality securities. The fund may face a heightened level of interest rate risk due to certain changes in general economic conditions, inflation and monetary policy, such as certain types of interest rate changes by the Federal Reserve. Any such changes could be sudden and could expose debt markets to significant volatility and reduced liquidity for fund investments.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US Government securities risk:</span> There are different types of US government securities with different levels of credit risk, including the risk of default, depending on the nature of the particular government support for that security. Securities issued or guaranteed by the US Treasury are backed by the full faith and credit of the United States, but are guaranteed only as to the timely payment of interest and principal when held to maturity, and the market prices for such securities will fluctuate. Notwithstanding that these securities are backed by the full faith and credit of the United States, circumstances could arise that would prevent the timely payment of interest or principal, which could result in losses to the fund (e.g., Congressional debt ceiling impasses).</div>
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Market risk:</span> The risk that the market value of the fund’s investments may fluctuate, sometimes rapidly or unpredictably, as the markets fluctuate, which may affect the fund’s share price. Market risk may affect a single issuer, industry, or sector of the economy, or it may affect the market as a whole. Moreover, changing market, economic, political and social conditions in one country or geographic region could adversely impact market, economic, political and social conditions in other countries or regions.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Liquidity risk:</span> Although the fund invests in a diversified portfolio of high quality instruments, the fund’s investments may become less liquid as a result of market developments or adverse investor perception. If this happens, the fund’s ability to redeem its shares for cash may be affected.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Management risk:</span> The risk that the investment strategies, techniques and risk analyses employed by the advisor may not produce the desired results. Consequently, the fund may underperform in comparison to other funds with similar objectives and investment strategies.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">US withholding tax risk:</span> The fund generally seeks to invest in securities the income from which is considered “qualified interest income” under relevant tax law and guidance. Thus, the fund generally expects its distributions to be exempt from US withholding tax when paid to non-US investors. However, there can be no assurance that any or all of the fund’s distributions will be exempt from US withholding tax.</div>
<div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;"><span style="font-weight: bold;">Technology risk: </span>Although the fund does not currently employ blockchain technology, financial intermediaries through whom shareholders purchase and redeem Token-Enabled Shares intend to employ blockchain technology to maintain a record or a mirror record of share ownership for their customers. A blockchain is a type of distributed ledger technology that records transactions between parties in a verifiable and append-only manner using cryptography. Transactions on the blockchain are verified and authenticated by computers on the network. The process of authenticating a transaction before it is recorded seeks to ensure that only valid and authorized transactions are permanently recorded on the blockchain in collections of transactions called “blocks.” Blockchain networks are based upon software source code that establishes and governs their respective cryptographic systems for verifying transactions. Complex information technology and communications systems, such as blockchain networks, are subject to a number of different threats or risks (including operational, information security, cyber-attacks and related risks) that could adversely affect the fund, its shareholders and financial intermediaries through whom shareholders purchase and redeem Token-Enabled Shares of the fund. The use of distributed ledger technology, including blockchain, is relatively new and still evolving. The fund, its transfer agent, advisor, distributor and their affiliates will not be responsible for any loss in connection with the use of blockchain technology by a financial intermediary subject to applicable law. Shareholders should contact their financial intermediaries about whether or how they use blockchain technology and the associated risks.</div>
Performance Risk/return bar chart and table
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The performance information that follows shows the fund’s performance information in a bar chart and an average annual total returns table for Institutional Shares of the fund, which is not offered in this</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">prospectus. There is no performance information quoted for Token-Enabled Shares of the fund as Token-Enabled Shares have not completed a full calendar year of operations as of the date of this prospectus. Although Token-Enabled Shares are invested in the same portfolio of securities as Institutional Shares, returns for Token-Enabled Shares will differ from Institutional Shares to the extent that there may be any differing expenses of the classes.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">The information provides some indication of the risks of investing in the fund by showing the fund’s performance over its first calendar year of operations. The fund’s past performance does not necessarily indicate how the fund will perform in the future.</div>
The performance information that follows shows the fund’s performance information in a bar chart and an average annual total returns table for Institutional Shares of the fund, which is not offered in this prospectus.
There is no performance information quoted for Token-Enabled Shares of the fund as Token-Enabled Shares have not completed a full calendar year of operations as of the date of this prospectus.
The information provides some indication of the risks of investing in the fund by showing the fund’s performance over its first calendar year of operations.
The fund’s past performance does not necessarily indicate how the fund will perform in the future.
UBS Select 100% US Treasury Institutional Fund Annual total return of Institutional Shares (2025 was the fund’s first full calendar year of operations)
<div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Total return January 1 to June 30, 2026: 1.75%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Best quarter during year shown—3Q 2025: 1.03%</div> <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Worst quarter during year shown—4Q 2025: 0.94%</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">Updated performance information is available (1) by contacting your Financial Advisor, (2) by calling 1‑888‑793 8637 (Option #1) and (3) on the fund’s website at https://www.ubs.com/usmoneymarketfunds.</div>
Total return
2026-06-30
0.0175
Best quarter
2025-09-30
0.0103
Worst quarter
2025-12-31
0.0094
1‑888‑793 8637
https://www.ubs.com/usmoneymarketfunds
Average annual total returns of Institutional Shares (for the periods ended December 31, 2025)
0.0407
2024-03-13
0.0447
Under its agreement with UBS Asset Management (Americas) LLC (“UBS AM”), the fund reimburses UBS AM for its direct costs and expenses incurred in managing the fund’s portfolio, which are included in “Management fees” above. “Management fees” have been restated to reflect amounts for the current fiscal year. The fund also reimburses UBS AM for its direct costs and expenses in administering the fund. UBS AM’s direct costs for management and administration services exclude any costs attributable to overhead or any profit charge.
The fund invests in securities through an underlying master fund, 100% US Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of 100% US Treasury Master Fund, including management fees allocated from 100% US Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.
The fund and UBS Asset Management (Americas) LLC (“UBS AM”) have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS AM is contractually obligated to waive its management fees and/or reimburse the fund so that the operating expenses of each class through August 31, 2027 (excluding interest expense, if any, expenses related to shareholders’ meetings and extraordinary items) would not exceed 0.14%. The fund has agreed to repay UBS AM for any waived management fees/reimbursed expenses to the extent that it can do so over the three years following such waived fees/reimbursed expenses without causing the fund’s expenses in any of those three years to exceed the lesser of any applicable expense limit that is in place for the fund (i) at the time of the waiver or reimbursement, or (ii) at the time of recoupment. The fee waiver/expense reimbursement agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s contract with UBS AM. Upon termination of the agreement, however, UBS AM’s three year recoupment rights will survive.
Inception date of Class T and Class P shares was March 13, 2024 and June 28, 2024, respectively.
The fund invests in securities through an underlying master fund, Prime CNAV Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime CNAV Master Fund, including management fees allocated from Prime CNAV Master Fund. Management fees are comprised of investment advisory and administration fees.
“Other expenses” do not include miscellaneous expenses, such as trustee expenses, which are deducted from the amount the fund pays UBS Asset Management (Americas) LLC (“UBS AM”). These other expenses are expected to be less than 0.01% of the average daily net assets of the fund.
The fund invests in securities through an underlying master fund, Prime CNAV Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Prime CNAV Master Fund, including management fees allocated from Prime CNAV Master Fund. Management fees are comprised of investment advisory and administration fees.
“Other expenses” do not include miscellaneous expenses, such as trustee expenses, which are deducted from the amount the fund pays UBS Asset Management (Americas) LLC (“UBS AM”). These other expenses are expected to be less than 0.01% of the average daily net assets of the fund.
The fund and UBS AM have entered into a written fee waiver agreement pursuant to which UBS AM is contractually obligated to waive its management fees so that the total ordinary operating expenses of the fund through August 31, 2027, do not exceed 0.14%. The fee waiver agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s contract with UBS AM.
Shares of the fund acquired through the exchange of shares of another Family Fund (“Family Funds” include PACE® Select funds, series of The UBS Funds and other funds for which UBS Asset Management (US) Inc. serves as principal underwriter) may be subject to a deferred sales charge if you later sell the fund shares acquired in the exchange, based on the terms of the shares of the Family Fund you originally held.
The fund and UBS Asset Management (Americas) LLC (“UBS AM”) have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS AM is contractually obligated to waive its management fee and/or reimburse expenses so that the fund’s ordinary total operating expenses of each class through August 31, 2027 (excluding dividend expense, borrowing costs, and interest expense relating to short sales, and expenses attributable to investment in other investment companies, interest, taxes, brokerage commissions, expenses related to shareholders’ meetings and extraordinary expenses) would not exceed 0.35% for Class A and 0.25% for Class P. The fund has agreed to repay UBS AM for any waived fees/reimbursed expenses to the extent that it can do so over the following three fiscal years without causing the class expenses in any of those three years to exceed these expense caps and that UBS AM has not waived the right to do so. The fee waiver/expense reimbursement agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s advisory contract with UBS AM. Upon termination of the agreement, however, UBS AM’s three year recoupment rights will survive.
Inception date of Class A and Class P shares was May 29, 2018.
The Bloomberg US Aggregate Bond Index is a broad representation of the investment-grade fixed-income market in the United States and includes US government and corporate debt securities, mortgage- and asset-backed securities, and international US dollar-denominated bonds. All securities contained in the Bloomberg US Aggregate Bond Index have a minimum term to maturity of one year.
ICE BofA 3-Month US Treasury Bill Index is comprised of a single issue purchased at the beginning of the month and held for a full month. At the end of the month that issue is sold and rolled into a newly selected issue. The issue selected at each month-end rebalancing is the outstanding Treasury Bill that matures closest to, but not beyond, three months from the rebalancing date. To qualify for selection, an issue must have settled on or before the month-end rebalancing date.
The fund and UBS Asset Management (Americas) LLC (“UBS AM”) have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS AM is contractually obligated to waive its management fee and/or reimburse expenses so that the fund’s ordinary total operating expenses through August 31, 2027 (excluding dividend expense, borrowing costs, and interest expense relating to short sales, and expenses attributable to investment in other investment companies, interest, taxes, brokerage commissions, expenses related to shareholders’ meetings and extraordinary expenses) would not exceed 0.23% for Class I. The fund has agreed to repay UBS AM for any waived fees/reimbursed expenses to the extent that it can do so over the following three fiscal years without causing the class expenses in any of those three years to exceed this expense cap and that UBS AM has not waived the right to do so. The fee waiver/expense reimbursement agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s advisory contract with UBS AM. Upon termination of the agreement, however, UBS AM’s three year recoupment rights will survive.
Inception date of Class I shares was May 29, 2018.
The Bloomberg US Aggregate Bond Index is a broad representation of the investment-grade fixed-income market in the United States and includes US government and corporate debt securities, mortgage- and asset-backed securities, and international US dollar-denominated bonds. All securities contained in the Bloomberg US Aggregate Bond Index have a minimum term to maturity of one year.
ICE BofA 3-Month US Treasury Bill Index is comprised of a single issue purchased at the beginning of the month and held for a full month. At the end of the month that issue is sold and rolled into a newly selected issue. The issue selected at each month-end rebalancing is the outstanding Treasury Bill that matures closest to, but not beyond, three months from the rebalancing date. To qualify for selection, an issue must have settled on or before the month-end rebalancing date.
The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund. Management fees are comprised of investment advisory and administration fees.
The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund. Management fees are comprised of investment advisory and administration fees.
The fund and UBS Asset Management (Americas) LLC (“UBS AM”), the fund’s investment advisor, have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS AM is contractually obligated to waive its management fees and/or reimburse the fund so that the fund’s operating expenses through August 31, 2027 (excluding interest expense, if any, expenses related to shareholders’ meetings and extraordinary items) would not exceed 0.30% for Investor Shares and 0.18% for Institutional Shares. The fund and UBS Asset Management (US) Inc. (“UBS AM (US)”) have entered into a written fee waiver agreement pursuant to which UBS AM (US) is contractually obligated to waive 0.15% of its shareholder servicing fee for Investor Shares also through August 31, 2027. The impact of both arrangements is reflected in the above table. The fund has agreed to repay UBS AM for any waived management fees/reimbursed expenses to the extent that it can do so over the three years following such waived fees/reimbursed expenses without causing the fund’s expenses in any of those three years to exceed the lesser of any applicable expense limit that is in place for the fund (i) at the time of the waiver or reimbursement, or (ii) at the time of recoupment. The fee waiver/expense reimbursement agreements may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s contract with UBS AM. Upon termination of the agreement, however, UBS AM’s three year recoupment rights will survive.
Inception date of Institutional Shares and Investor Shares was March 25, 2024 and January 16, 2024, respectively.
The fund invests in securities through an underlying master fund, 100% US Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of 100% US Treasury Master Fund, including management fees allocated from 100% US Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.
The Fund’s “Other Expenses” have been estimated to reflect expenses to be incurred during the first fiscal year.
The fund and UBS Asset Management (Americas) LLC (“UBS AM”) have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS AM is contractually obligated to waive its management fees and/or reimburse the fund so that the fund’s operating expenses through August 31, 2027 (excluding interest expense, if any, expenses related to shareholders’ meetings and extraordinary items) would not exceed 0.18%. The fund has agreed to repay UBS AM for any waived management fees/reimbursed expenses to the extent that it can do so over the three years following such waived fees/reimbursed expenses without causing the fund’s expenses in any of those three years to exceed the lesser of any applicable expense limit that is in place for the fund (i) at the time of the waiver or reimbursement, or (ii) at the time of recoupment. The fee waiver/expense reimbursement agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s contract with UBS AM. Upon termination of the agreement, however, UBS AM’s three year recoupment rights will survive.
The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund. Management fees are comprised of investment advisory and administration fees.
“Other expenses” do not include miscellaneous expenses, such as trustee expenses, which are deducted from the amount the fund pays UBS Asset Management (Americas) LLC (“UBS AM”). These other expenses are expected to be less than 0.01% of the average daily net assets of the fund.
The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.
“Other expenses” do not include miscellaneous expenses, such as trustee expenses, which are deducted from the amount the fund pays UBS Asset Management (Americas) LLC (“UBS AM”). These other expenses are expected to be less than 0.01% of the average daily net assets of the fund.
The fund invests in securities through an underlying master fund, 100% US Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of 100% US Treasury Master Fund, including management fees allocated from 100% US Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.
The fund and UBS Asset Management (Americas) LLC (“UBS AM”) have entered into a written fee waiver/expense reimbursement agreement pursuant to which UBS AM is contractually obligated to waive its management fees and/or reimburse the fund so that the fund’s operating expenses through August 31, 2027 (excluding interest expense, if any, expenses related to shareholders’ meetings and extraordinary items) would not exceed 0.18% for Institutional Shares. The fund has agreed to repay UBS AM for any waived management fees/reimbursed expenses to the extent that it can do so over the three years following such waived fees/reimbursed expenses without causing the fund’s expenses in any of those three years to exceed the lesser of any applicable expense limit that is in place for the fund (i) at the time of the waiver or reimbursement, or (ii) at the time of recoupment. The fee waiver/expense reimbursement agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s contract with UBS AM. Upon termination of the agreement, however, UBS AM’s three year recoupment rights will survive.
The fund invests in securities through an underlying master fund, Government Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Government Master Fund, including management fees allocated from Government Master Fund. Management fees are comprised of investment advisory and administration fees.
“Other expenses” do not include miscellaneous expenses, such as trustee expenses, which are deducted from the amount the fund pays UBS Asset Management (Americas) LLC (“UBS AM”). These other expenses are expected to be less than 0.01% of the average daily net assets of the fund.
The fund and UBS AM have entered into a written fee waiver agreement pursuant to which UBS AM is contractually obligated to waive its management fees so that the total ordinary operating expenses of the fund through August 31, 2027, do not exceed 0.14%. The fee waiver agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s contract with UBS AM.
The fund invests in securities through an underlying master fund, Treasury Master Fund. This table reflects the direct expenses of the fund and its share of expenses of Treasury Master Fund, including management fees allocated from Treasury Master Fund. Management fees are comprised of investment advisory and administration fees.
“Other expenses” do not include miscellaneous expenses, such as trustee expenses, which are deducted from the amount the fund pays UBS Asset Management (Americas) LLC (“UBS AM”). These other expenses are expected to be less than 0.01% of the average daily net assets of the fund.
The fund and UBS AM have entered into a written fee waiver agreement pursuant to which UBS AM is contractually obligated to waive its management fees so that the total ordinary operating expenses of the fund through August 31, 2027, do not exceed 0.14%. The fee waiver agreement may be terminated by the fund’s board at any time and also will terminate automatically upon the expiration or termination of the fund’s contract with UBS AM.