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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 0 0 Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0010 0.0010 0.0010 0 0 0 0.0022 0.0022 0.0022 0.0015 0.0015 0.0015 0.0007 0.0007 0.0007 0.0032 0.0032 0.0032 0.0014 0.0018 0.0024 0.0018 0.0014 0.0008 “Other expenses” are based on estimated 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. 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 89 14 85 8 79 <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;">*Except</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;">that the expenses reflect the effects of the fund’s fee waiver/expense reimbursement agreement for the first year only.</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 intends to invest only in certain eligible reserve assets that payment stablecoin issuers are permitted to maintain under the Guiding and Establishing National Innovation for US Stablecoins Act (the “GENIUS Act”) and any effective regulation adopted thereunder. These eligible reserve assets include, and the fund intends to invest only in, cash, securities issued by the US Treasury with a remaining maturity of 93 days or less or issued with a maturity of 93 days or less, and overnight repurchase agreements collateralized by securities issued by the US Treasury and cash. The fund primarily intends to serve as a reserve asset for stablecoin issuers. The fund does not invest in stablecoins or stablecoin issuers.</div> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">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.</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 overnight 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 on or before the next day 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; 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> <div style="margin-top: 12pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">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.</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 overnight 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 on or before the next day 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. 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.</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;">Stablecoin issuer reserves risk: </span>Shares of the fund are expected to be held primarily by one or more stablecoin issuers as all or a portion of the reserve assets that back the outstanding stablecoins issued to their customers. Stablecoins generally are a type of cryptocurrency that are designed to maintain a stable value by pegging their value to another asset, such as a fiat currency like the US dollar, and stablecoin holders generally are permitted to redeem their stablecoins for a fixed amount of value. Although the fund does not invest in stablecoins or stablecoin issuers, the assets of the fund are expected to fluctuate depending on the creation (minting) of additional stablecoins or the redemption (burning) of outstanding stablecoins. Stablecoins and other digital assets that stablecoins may be used to purchase or sell may face periods of uncertainty and volatility that result in the potential for rapid or unexpected requests by one or more stablecoin issuers to redeem or purchase the fund’s shares. Such redemption requests could adversely affect remaining fund shareholders, the fund’s liquidity, and the fund’s ability to maintain a stable price per share, particularly if such redemptions occur in times of overall market turmoil or declining prices. Uncertainty or volatility may result from events that are not specifically related to a stablecoin issuer, such as changes in general market conditions, economic, technological or legal trends or changes to the laws or regulation of stablecoins, or events that are specifically related to a particular stablecoin issuer, such as uncertainty about the stablecoin issuer’s ability to maintain a consistent peg between the stablecoins issued to its customers and another asset, such as a fiat currency like the US dollar. Because the fund intends to invest only in certain eligible reserve assets that payment stablecoin issuers are permitted to maintain under the GENIUS Act, the fund’s yield may be lower than other money market funds that are permitted to invest in a wider universe of investments and with longer maturities.</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 <div style="margin-top: 0pt; margin-bottom: 0pt; font-size: 10pt; font-family: arial;">There is no performance information quoted for the fund as the fund had not yet commenced operations as of the date of this prospectus.</div> There is no performance information quoted for the fund as the fund had not yet commenced operations as of the date of this prospectus. 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 (i) waive 0.05% of its management fee for each class and (ii) waive fees and/or reimburse expenses so that the total ordinary operating expenses of the fund through August 12, 2027, do not exceed 0.18% for Institutional Shares, 0.14% for Preferred Shares, and 0.08% for Ultra Shares (the “Expense Limitation”). As part of this overall limitation, 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 a portion of its shareholder servicing fee equal to 0.04% for Institutional Shares, 0.08% for Preferred Shares, and 0.14% for Ultra Shares through August 12, 2027. The UBS AM (US) shareholder servicing fee waiver contributes to, and does not supplement, the Expense Limitation set forth herein. The impact of both arrangements is reflected in the above table. The fund has agreed to repay UBS AM for any waived 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. “Other expenses” are based on estimated amounts for the current fiscal year.