Prospectus - Investment Objective

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM N-CSR

CERTIFIED SHAREHOLDER REPORT OF REGISTERED

MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number 811-06440

Fidelity Aberdeen Street Trust

(Exact name of registrant as specified in charter)

245 Summer St., Boston, MA 02210

(Address of principal executive offices) (Zip code)

Nicole Macarchuk, Secretary

245 Summer St.

Boston, Massachusetts 02210

(Name and address of agent for service)

Registrant's telephone number, including area code:

617-563-7000


Date of fiscal year end:	February 28

Date of reporting period:	August 31, 2025

Item 1.

Reports to Stockholders


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® Multi-Asset Index Fund Fidelity® Multi-Asset Index Fund : FFNOX

This semi-annual shareholder report contains information about Fidelity® Multi-Asset Index Fund for the period March 1, 2025 to August 31, 2025. You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.

What were your Fund costs for the last six months?

(based on hypothetical $10,000 investment)

	Costs of a $10,000 investment	Costs paid as a percentage of a $10,000 investment
Fidelity® Multi-Asset Index Fund	$ 4	0.08%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$9,136,104,769
Number of Holdings	7
Portfolio Turnover	15%

What did the Fund invest in?
(as of August 31, 2025)

ASSET ALLOCATION (% of Fund's net assets)

	Domestic Equity Funds - 51.0
	International Equity Funds - 34.0
	Bond Funds - 15.0
	Short-Term Investments and Net Other Assets (Liabilities) - 0.0

TOP HOLDINGS (% of Fund's net assets)
Fidelity 500 Index Fund	41.0
Fidelity International Index Fund	24.0
Fidelity Extended Market Index Fund	10.0
Fidelity Emerging Markets Index Fund	10.0
Fidelity U.S. Bond Index Fund	7.0
Fidelity Long-Term Treasury Bond Index Fund	5.0
Fidelity International Bond Index Fund	3.0
	100.0

Fidelity, the Fidelity Investments Logo and all other Fidelity trademarks or service marks used herein are trademarks or service marks of FMR LLC. Any third-party marks that are used herein are trademarks or service marks of their respective owners. © 2025 FMR LLC. All rights reserved.
		For additional information about the Fund; including its prospectus, financial information, holdings and proxy information, scan the QR code or visit fundresearch.fidelity.com/prospectus/sec 1.9914531.101 355-TSRS-1025

Item 2.

Code of Ethics

Not applicable.

Item 3.

Audit Committee Financial Expert

Not applicable.

Item 4.

Principal Accountant Fees and Services

Not applicable.

Item 5.

Audit Committee of Listed Registrants

Not applicable.

Item 6.

Investments

(a)

Not applicable.

(b)

Not applicable

Item 7.

Financial Statements and Financial Highlights for Open-End Management Investment Companies

Fidelity® Multi-Asset Index Fund

Semi-Annual Report

August 31, 2025

Contents

Item 7: Financial Statements and Financial Highlights for Open-End Management Investment Companies (Semi-Annual Report)

Fidelity® Multi-Asset Index Fund

Notes to Financial Statements

Item 8: Changes in and Disagreements with Accountants for Open-End Management Investment Companies

Item 9: Proxy Disclosures for Open-End Management Investment Companies

Item 10: Remuneration Paid to Directors, Officers, and others of Open-End Management Investment Companies

Item 11: Statement Regarding Basis for Approval of Investment Advisory Contract

To view a fund's proxy voting guidelines and proxy voting record for the 12-month period ended June 30, visit http://www.fidelity.com/proxyvotingresults or visit the Securities and Exchange Commission's (SEC) web site at http://www.sec.gov.

You may also call 1-800-544-8544 to request a free copy of the proxy voting guidelines.

The index is a product of S&P Dow Jones Indices LLC or its affiliates ("SPDJI") and has been licensed for us by Fidelity. S&P®;, S&P 500®, US 500, The 500, iBoxx®, iTraxx® and CDX® are trademarks of S&P Global, Inc. or its affiliates ("S&P") and Dow Jones®; is a registered trademark of Dow Jones Trademark Holdings LLC ("Dow Jones"). The fund is not sponsored, endorsed, sold or promoted by SPDJI, Dow Jones, S&P, or their respective affiliates and none of such parties make any representation regarding the advisability of investing in such product(s) nor do they have any liability for any errors, omissions, or interruptions of the index or indices.

Standard & Poor's, S&P and S&P 500 are registered service marks of The McGraw-Hill Companies, Inc. and have been licensed for use by Fidelity Distributors Corporation.

Other third-party marks appearing herein are the property of their respective owners.

This report and the financial statements contained herein are submitted for the general information of the shareholders of the Fund. This report is not authorized for distribution to prospective investors in the Fund unless preceded or accompanied by an effective prospectus.

A fund files its complete schedule of portfolio holdings with the SEC for the first and third quarters of each fiscal year on Form N-PORT. Forms N-PORT are available on the SEC's web site at http://www.sec.gov. A fund's Forms N-PORT may be reviewed and copied at the SEC's Public Reference Room in Washington, DC. Information regarding the operation of the SEC's Public Reference Room may be obtained by calling 1-800-SEC-0330.

For a complete list of a fund's portfolio holdings, view the most recent holdings listing, semiannual report, or annual report on Fidelity's web site at http://www.fidelity.com, http://www.institutional.fidelity.com, or http://www.401k.com, as applicable.

NOT FDIC INSURED •MAY LOSE VALUE •NO BANK GUARANTEE

Neither the Fund nor Fidelity Distributors Corporation is a bank.

Item 7: Financial Statements and Financial Highlights for Open-End Management Investment Companies (Semi-Annual Report)

Fidelity® Multi-Asset Index Fund

Schedule of Investments August 31, 2025 (Unaudited)

Showing Percentage of Net Assets

Bond Funds - 15.0%
	Shares	Value ($)
Fidelity International Bond Index Fund (a)	29,269,878	273,380,661
Fidelity Long-Term Treasury Bond Index Fund (a)	49,803,014	456,693,641
Fidelity U.S. Bond Index Fund (a)	61,138,178	640,116,728
TOTAL BOND FUNDS (Cost $1,550,859,206)		1,370,191,030

Domestic Equity Funds - 51.0%
	Shares	Value ($)
Fidelity 500 Index Fund (a)	16,649,737	3,742,194,851
Fidelity Extended Market Index Fund (a)	9,267,157	918,097,279
TOTAL DOMESTIC EQUITY FUNDS (Cost $999,201,048)		4,660,292,130

International Equity Funds - 34.0%
	Shares	Value ($)
Fidelity Emerging Markets Index Fund (a)	72,883,051	913,953,459
Fidelity International Index Fund (a)	37,423,513	2,192,269,382
TOTAL INTERNATIONAL EQUITY FUNDS (Cost $2,136,062,563)		3,106,222,841

TOTAL INVESTMENT IN SECURITIES - 100.0% (Cost $4,686,122,817)	9,136,706,001
NET OTHER ASSETS (LIABILITIES) - 0.0%	(601,232)
NET ASSETS - 100.0%	9,136,104,769

Legend

(a)	Affiliated Fund

Affiliated Underlying Funds

Fiscal year to date information regarding the Fund's investments in affiliated underlying funds is presented below. Exchanges between classes of the same affiliated underlying funds may occur. If an underlying fund changes its name, the name presented below is the name in effect at period end.

Affiliate	Value, beginning of period ($)	Purchases ($)	Sales Proceeds ($)	Dividend Income ($)	Realized Gain (loss) ($)	Change in Unrealized appreciation (depreciation) ($)	Value, end of period ($)	Shares, end of period
Fidelity 500 Index Fund	3,493,094,226	238,061,652	291,079,157	21,193,960	9,754,169	292,363,961	3,742,194,851	16,649,737
Fidelity Emerging Markets Index Fund	837,305,683	24,146,467	80,137,227	-	(6,662,598)	139,301,134	913,953,459	72,883,051
Fidelity Extended Market Index Fund	850,402,135	58,628,308	80,870,469	-	1,055,136	88,882,169	918,097,279	9,267,157
Fidelity International Bond Index Fund	252,083,640	33,945,501	12,005,794	3,017,451	(121,791)	(520,895)	273,380,661	29,269,878
Fidelity International Index Fund	2,024,564,172	131,067,288	232,216,086	-	25,551,904	243,302,104	2,192,269,382	37,423,513
Fidelity Long-Term Treasury Bond Index Fund	423,721,615	75,247,670	22,064,919	8,266,772	(9,456,599)	(10,754,126)	456,693,641	49,803,014
Fidelity U.S. Bond Index Fund	590,299,462	82,205,076	34,531,306	10,809,215	(1,857,003)	4,000,499	640,116,728	61,138,178
	8,471,470,933	643,301,962	752,904,958	43,287,398	18,263,218	756,574,846	9,136,706,001

Amounts in the dividend income column in the above table include any capital gain distributions from underlying funds, which are presented in the corresponding line item in the Statement of Operations, if applicable.

Amounts included in the purchases and sales proceeds columns may include in-kind transactions, if applicable.

Investment Valuation

The following is a summary of the inputs used, as of August 31, 2025, involving the Fund's assets and liabilities carried at fair value. The inputs or methodology used for valuing securities may not be an indication of the risk associated with investing in those securities. For more information on valuation inputs, and their aggregation into the levels used below, please refer to the Investment Valuation section in the accompanying Notes to Financial Statements.

Valuation Inputs at Reporting Date:
Description	Total ($)	Level 1 ($)	Level 2 ($)	Level 3 ($)
Investments in Securities:

Bond Funds	1,370,191,030	1,370,191,030	-	-

Domestic Equity Funds	4,660,292,130	4,660,292,130	-	-

International Equity Funds	3,106,222,841	3,106,222,841	-	-
Total Investments in Securities:	9,136,706,001	9,136,706,001	-	-

Financial Statements (Unaudited)

Statement of Assets and Liabilities
As of August 31, 2025 (Unaudited)
Assets
Investment in securities, at value - See accompanying schedule:
Affiliated issuers (cost $4,686,122,817)	$	9,136,706,001


Total Investment in Securities (cost $4,686,122,817)			$	9,136,706,001
Receivable for investments sold				42,881,568
Receivable for fund shares sold				3,170,600
Receivable from investment adviser for expense reductions				151,372
Total assets				9,182,909,541
Liabilities
Payable for investments purchased	$	43,693,188
Payable for fund shares redeemed		2,355,367
Accrued management fee		756,217
Total liabilities				46,804,772
Net Assets			$	9,136,104,769
Net Assets consist of:
Paid in capital			$	4,713,033,823
Total accumulated earnings (loss)				4,423,070,946
Net Assets			$	9,136,104,769
Net Asset Value, offering price and redemption price per share ($9,136,104,769 ÷ 142,084,177 shares)			$	64.30

Statement of Operations
Six months ended August 31, 2025 (Unaudited)
Investment Income
Dividends:
Affiliated issuers			$	43,287,398
Expenses
Management fee	$	4,256,584
Independent trustees' fees and expenses		9,751
Total expenses before reductions		4,266,335
Expense reductions		(853,952)
Total expenses after reductions				3,412,383
Net Investment income (loss)				39,875,015
Realized and Unrealized Gain (Loss)
Net realized gain (loss) on:
Investment Securities:
Affiliated issuers		18,263,218
Total net realized gain (loss)				18,263,218
Change in net unrealized appreciation (depreciation) on:
Investment Securities:
Affiliated issuers		756,574,846
Total change in net unrealized appreciation (depreciation)				756,574,846
Net gain (loss)				774,838,064
Net increase (decrease) in net assets resulting from operations			$	814,713,079

Statement of Changes in Net Assets

		Six months ended August 31, 2025 (Unaudited)		Year ended February 28, 2025
Increase (Decrease) in Net Assets
Operations
Net investment income (loss)	$	39,875,015	$	170,078,803
Net realized gain (loss)		18,263,218		348,128,473
Change in net unrealized appreciation (depreciation)		756,574,846		487,522,697
Net increase (decrease) in net assets resulting from operations		814,713,079		1,005,729,973
Distributions to shareholders		(139,041,681)		(516,236,808)

Share transactions
Proceeds from sales of shares		368,401,197		604,083,711
Reinvestment of distributions		126,025,263		468,431,390
Cost of shares redeemed		(504,896,237)		(1,132,820,229)

Net increase (decrease) in net assets resulting from share transactions		(10,469,777)		(60,305,128)
Total increase (decrease) in net assets		665,201,621		429,188,037

Net Assets
Beginning of period		8,470,903,148		8,041,715,111
End of period	$	9,136,104,769	$	8,470,903,148

Other Information
Shares
Sold		6,122,038		10,240,918
Issued in reinvestment of distributions		2,315,364		8,189,713
Redeemed		(8,512,308)		(19,138,895)
Net increase (decrease)		(74,906)		(708,264)

Financial Highlights

Fidelity® Multi-Asset Index Fund

		Six months ended August 31, 2025 (Unaudited)		Years ended February 28, 2025		2024 A		2023		2022		2021
Selected Per-Share Data
Net asset value, beginning of period	$	59.59	$	56.29	$	48.92	$	56.99	$	56.29	$	45.60
Income from Investment Operations
Net investment income (loss) B,C		.28		1.20		1.11		.94		1.14		.86
Net realized and unrealized gain (loss)		5.42		5.81		7.99		(5.65)		3.06		11.42
Total from investment operations		5.70		7.01		9.10		(4.71)		4.20		12.28
Distributions from net investment income		(.03)		(1.24)		(1.10)		(.96)		(1.14)		(.88)
Distributions from net realized gain		(.95)		(2.48)		(.63)		(2.40)		(2.35)		(.70)
Total distributions		(.99) D		(3.71) D		(1.73)		(3.36)		(3.50) D		(1.59) D
Net asset value, end of period	$	64.30	$	59.59	$	56.29	$	48.92	$	56.99	$	56.29
Total Return E,F		9.86 %		12.82%		18.72%		(8.43)%		7.07%		27.10%
Ratios to Average Net Assets C,G,H
Expenses before reductions		.10% I		.10%		.10%		.10%		.10%		.10%
Expenses net of fee waivers, if any		.08 % I		.08%		.08%		.08%		.08%		.08%
Expenses net of all reductions, if any		.08% I		.08%		.08%		.08%		.08%		.08%
Net investment income (loss)		.93% I		2.03%		2.13%		1.89%		1.87%		1.73%
Supplemental Data
Net assets, end of period (000 omitted)	$	9,136,105	$	8,470,903	$	8,041,715	$	7,185,984	$	8,314,829	$	7,597,894
Portfolio turnover rate J		15 % I		12%		10%		17%		28%		16%

AFor the year ended February 29.

BCalculated based on average shares outstanding during the period.

CNet investment income (loss) is affected by the timing of the declaration of dividends by any underlying mutual funds or exchange-traded funds (ETFs). Net investment income (loss) of any mutual funds or ETFs is not included in the Fund's net investment income (loss) ratio.

DTotal distributions per share do not sum due to rounding.

ETotal returns for periods of less than one year are not annualized.

FTotal returns would have been lower if certain expenses had not been reduced during the applicable periods shown.

GFees and expenses of any underlying mutual funds or exchange-traded funds (ETFs) are not included in the Fund's expense ratio. The Fund indirectly bears its proportionate share of these expenses.

HExpense ratios reflect operating expenses of the class. Expenses before reductions do not reflect amounts reimbursed, waived, or reduced through arrangements with the investment adviser, brokerage services, or other offset arrangements, if applicable, and do not represent the amount paid by the class during periods when reimbursements, waivers or reductions occur.

IAnnualized.

JAmount does not include the portfolio activity of any underlying mutual funds or exchange-traded funds (ETFs), derivatives or securities that mature within one year from acquisition.

Notes to Financial Statements

(Unaudited)

For the period ended August 31, 2025

1. Organization.

Fidelity Multi-Asset Index Fund (the Fund) is a fund of Fidelity Aberdeen Street Trust (the Trust) and is authorized to issue an unlimited number of shares. Share transactions on the Statement of Changes in Net Assets may contain exchanges between affiliated funds. The Trust is registered under the Investment Company Act of 1940, as amended (the 1940 Act), as an open-end management investment company organized as a Delaware statutory trust. Geode Capital Management, LLC serves as sub-adviser for the underlying stock funds.

The Fund is a fund of funds, and therefore invests in other funds instead of individual securities. The Fund invests primarily in a combination of Fidelity stock and bond index funds.

2. Significant Accounting Policies.

The Fund is an investment company and applies the accounting and reporting guidance of the Financial Accounting Standards Board (FASB) Accounting Standards Codification Topic 946 Financial Services - Investment Companies. The financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (GAAP), which require management to make certain estimates and assumptions at the date of the financial statements. Actual results could differ from those estimates. The Fund operates as a single operating segment. The Fund's income, expenses, assets, and performance are regularly monitored and assessed as a whole by the investment adviser and other individuals responsible for oversight functions of the Trust, using the information presented in the financial statements and financial highlights. Subsequent events, if any, through the date that the financial statements were issued have been evaluated in the preparation of the financial statements. The Fund's Schedule of Investments lists any underlying mutual funds or exchange-traded funds but does not include the underlying holdings of these funds. The following summarizes the significant accounting policies of the Fund:

Investment Valuation. Investments are valued as of 4:00 p.m. Eastern time on the last calendar day of the period. The Fund categorizes the inputs to valuation techniques used to value its investments into a disclosure hierarchy consisting of three levels as shown below:

Level 1 - unadjusted quoted prices in active markets for identical investments

Level 2 - other significant observable inputs (including quoted prices for similar investments, interest rates, prepayment speeds, etc.)

Level 3 - unobservable inputs (including the Fund's own assumptions based on the best information available)

Valuation techniques used to value the Fund's investments by major category are as follows:

Investments in open-end mutual funds are valued at their closing net asset value (NAV) each business day and are categorized as Level 1 in the hierarchy.

Investment Transactions and Income. For financial reporting purposes, the Fund's investment holdings and NAV include trades executed through the end of the last business day of the period. The NAV per share for processing shareholder transactions is calculated as of the close of business of the New York Stock Exchange (NYSE), normally 4:00 p.m. Eastern time and includes trades executed through the end of the prior business day. Gains and losses on securities sold are determined on the basis of identified cost. Income and capital gain distributions from any underlying mutual funds or exchange-traded funds are recorded on the ex-dividend date.

Expenses. Expenses directly attributable to a fund are charged to that fund. Expenses attributable to more than one fund are allocated among the respective funds on the basis of relative net assets or other appropriate methods. Expenses included in the accompanying financial statements reflect the expenses of that fund and do not include any expenses associated with any underlying mutual funds or exchange-traded funds. Although not included in a fund's expenses, a fund indirectly bears its proportionate share of these expenses through the net asset value of each underlying mutual fund or exchange-traded fund. Expense estimates are accrued in the period to which they relate and adjustments are made when actual amounts are known.

Income Tax Information and Distributions to Shareholders. Each year, the Fund intends to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code, including distributing substantially all of its taxable income and realized gains. As a result, no provision for U.S. Federal income taxes is required. The Fund files a U.S. federal tax return, in addition to state and local tax returns as required. The Fund's federal income tax returns are subject to examination by the Internal Revenue Service (IRS) for a period of three fiscal years after they are filed. State and local tax returns may be subject to examination for an additional fiscal year depending on the jurisdiction.

Distributions are declared and recorded on the ex-dividend date. Income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP.

Capital accounts within the financial statements are adjusted for permanent book-tax differences. These adjustments have no impact on net assets or the results of operations. Capital accounts are not adjusted for temporary book-tax differences which will reverse in a subsequent period.

Book-tax differences are primarily due to losses deferred due to wash sales.

As of period end, the cost and unrealized appreciation (depreciation) in securities, and derivatives if applicable, for federal income tax purposes were as follows:

Gross unrealized appreciation	$4,573,660,943
Gross unrealized depreciation	(206,702,706)
Net unrealized appreciation (depreciation)	$4,366,958,237
Tax cost	$4,769,747,764

New Accounting Pronouncement.

In December 2023, the FASB issued ASU 2023-09 Income Taxes (Topic 740): Improvements to Income Tax Disclosures. Effective for annual periods beginning after December 15, 2024, the amendments require greater disaggregation of disclosures related to income taxes paid. The ASU allows for early adoption and amendments should be applied on a prospective basis. Management is currently evaluating the impact of the ASU but does not expect this guidance to materially impact the financial statements.

3. Purchases and Sales of Investments.

Purchases and sales of securities, other than short-term securities and in-kind transactions, as applicable, are noted in the table below.

	Purchases ($)	Sales ($)
Fidelity Multi-Asset Index Fund	643,301,962	752,904,958

4. Fees and Other Transactions with Affiliates.

Management Fee. Fidelity Management & Research Company LLC (the investment adviser) provides the Fund with investment management related services. For these services the Fund pays a monthly management fee to the investment adviser. The management fee is computed at an annual rate of .10% of the Fund's average net assets. Under the management contract, the investment adviser pays all other operating expenses, except the compensation of the independent Trustees and certain other expenses such as interest expense. The management fee is reduced by an amount equal to the fees and expenses paid by the Fund to the independent Trustees.

Interfund Trades. Funds may purchase from or sell securities to other Fidelity Funds under procedures adopted by the Board of Trustees. The procedures have been designed to ensure these interfund trades are executed in accordance with Rule 17a-7 of the 1940 Act. Any interfund trades are included within the respective purchases and sales amounts shown in the Purchases and Sales of Investments note. During the period, there were no interfund trades.

5. Expense Reductions.

The investment adviser contractually agreed to reimburse the Fund to the extent annual operating expenses exceeded .08% of average net assets. This reimbursement will remain in place through June 30, 2026. Some expenses, for example the compensation of the independent Trustees, and certain miscellaneous expenses such as proxy and shareholder meeting expenses, are excluded from this reimbursement. During the period this reimbursement reduced the Fund's expenses by $853,867.

Through arrangements with the Fund's custodian, credits realized as a result of certain uninvested cash balances were used to reduce the Fund's expenses by $85.

6. Other.

A fund's organizational documents provide former and current trustees and officers with a limited indemnification against liabilities arising in connection with the performance of their duties to the fund. In the normal course of business, a fund may also enter into contracts that provide general indemnifications. A fund's maximum exposure under these arrangements is unknown as this would be dependent on future claims that may be made against a fund. The risk of material loss from such claims is considered remote.

Funds do not invest in underlying mutual funds for the purpose of exercising management or control; however, investments by funds within their principal investment strategies may represent a significant portion of the underlying mutual fund's net assets. At the end of the period, certain Funds were the owners of record of 10% or more of the total outstanding shares of the following underlying mutual funds as shown below.

Fund	Fidelity Multi-Asset Index Fund
Fidelity International Bond Index Fund	26%

7. Risk and Uncertainties.

Many factors affect a fund's performance. Developments that disrupt global economies and financial markets, such as public health emergencies, military conflicts, terrorism, government restrictions, political changes, and environmental disasters, may significantly affect a fund's investment performance. The effects of these developments to a fund will be impacted by the types of securities in which a fund invests, the financial condition, industry, economic sector, and geographic location of an issuer, and a fund's level of investment in the securities of that issuer. Significant concentrations in security types, issuers, industries, sectors, and geographic locations may magnify the factors that affect a fund's performance.

Item 8: Changes in and Disagreements with Accountants for Open-End Management Investment Companies

(Unaudited)

Note: This is not applicable for any fund included in this document.

Item 9: Proxy Disclosures for Open-End Management Investment Companies

(Unaudited)

Note: This is not applicable for any fund included in this document.

Item 10: Remuneration Paid to Directors, Officers, and others of Open-End Management Investment Companies

(Unaudited)

Note: This information is disclosed as part of the financial statements for each Fund as part of Item 7: Financial Statements and Financial Highlights for Open-End Management Investment Companies.

Item 11: Statement Regarding Basis for Approval of Investment Advisory Contract

(Unaudited)

Note: This is not applicable for any fund included in this document.

1.728266.126

IDV-SANN-1025

Item 8.

Changes in and Disagreements with Accountants for Open-End Management Investment Companies

See Item 7.

Item 9.

Proxy Disclosures for Open-End Management Investment Companies

See Item 7.

Item 10.

Remuneration Paid to Directors, Officers, and Others of Open-End Management Investment Companies

See Item 7.

Item 11.

Statement Regarding Basis for Approval of Investment Advisory Contract

See Item 7.

Item 12.

Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies

Not applicable.

Item 13.

Portfolio Managers of Closed-End Management Investment Companies

Not applicable.

Item 14.

Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers

Not applicable.

Item 15.

Submission of Matters to a Vote of Security Holders

There were no material changes to the procedures by which shareholders may recommend nominees to the Fidelity Aberdeen Street Trust’s Board of Trustees.

Item 16.

Controls and Procedures

(a)(i) The President and Treasurer and the Chief Financial Officer have concluded that the Fidelity Aberdeen Street Trust’s (the “Trust”) disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act) provide reasonable assurances that material information relating to the Trust is made known to them by the appropriate persons, based on their evaluation of these controls and procedures as of a date within 90 days of the filing date of this report.

(a)(ii) There was no change in the Trust’s internal control over financial reporting (as defined in Rule 30a-3(d) under the Investment Company Act) that occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the Trust’s internal control over financial reporting.

Item 17.

Disclosure of Securities Lending Activities for Closed-End Management Investment Companies

Not applicable.

Item 18.

Recovery of Erroneously Awarded Compensation

(a)

Not applicable.

(b)

Not applicable.

Item 19.

Exhibits


(a)	(1)	Not applicable.
(a)	(2)	Certification pursuant to Rule 30a-2(a) under the Investment Company Act of 1940 (17 CFR 270.30a-2(a)) is filed and attached hereto as Exhibit 99.CERT.
(a)	(3)	Not applicable.
(b)		Certification pursuant to Rule 30a-2(b) under the Investment Company Act of 1940 (17 CFR 270.30a-2(b)) is furnished and attached hereto as Exhibit 99.906CERT.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Fidelity Aberdeen Street Trust


By:	/s/Laura M. Del Prato
	Laura M. Del Prato
	President and Treasurer (Principal Executive Officer)

Date:	October 23, 2025

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.


By:	/s/Laura M. Del Prato
	Laura M. Del Prato
	President and Treasurer (Principal Executive Officer)

Date:	October 23, 2025


By:	/s/Stephanie Caron
	Stephanie Caron
	Chief Financial Officer (Principal Financial Officer)

Date:	October 23, 2025

ATTACHMENTS / EXHIBITS

ATTACHMENTS / EXHIBITS

IDEA: FilingSummary.xml

IDEA: MetaLinks.json

IDEA: filing9916_htm.xml

Domestic Equity Funds	51.0
International Equity Funds	34.0
Bond Funds	15.0
Short-Term Investments and Net Other Assets (Liabilities)	0.0