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 811-02105

Fidelity Salem 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® Short-Term Treasury Bond Index Fund Fidelity® Short-Term Treasury Bond Index Fund : FUMBX

This semi-annual shareholder report contains information about Fidelity® Short-Term Treasury Bond 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® Short-Term Treasury Bond Index Fund	$ 2	0.03%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$3,266,390,207
Number of Holdings	114
Portfolio Turnover	32%

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

COUPON DISTRIBUTION (% of Fund's net assets)
0.01 - 0.99%	12.9
1 - 1.99%	17.1
2 - 2.99%	8.4
3 - 3.99%	25.3
4 - 4.99%	34.7
5 - 5.99%	0.4
6 - 6.99%	0.5

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 99.3
	Short-Term Investments and Net Other Assets (Liabilities) - 0.7

TOP HOLDINGS (% of Fund's net assets)
US Treasury Notes	98.4
US Treasury Bonds	0.9
	99.3

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 1.9914565.101 3049-TSRS-1025


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® Series Long-Term Treasury Bond Index Fund Fidelity® Series Long-Term Treasury Bond Index Fund : FTLTX

This semi-annual shareholder report contains information about Fidelity® Series Long-Term Treasury Bond 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.

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® Series Long-Term Treasury Bond Index Fund	$ 0 A	0.00%B

A Amount represents less than $.50

B Amount represents less than 0.005%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$22,092,716,503
Number of Holdings	94
Portfolio Turnover	10%

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

COUPON DISTRIBUTION (% of Fund's net assets)
1 - 1.99%	8.2
2 - 2.99%	30.3
3 - 3.99%	26.2
4 - 4.99%	33.3
5 - 5.99%	1.1

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 99.1
	Short-Term Investments and Net Other Assets (Liabilities) - 0.9

TOP HOLDINGS (% of Fund's net assets)
US Treasury Bonds	98.2
US Treasury Notes	0.9
	99.1

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 1.9914574.101 2840-TSRS-1025


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® SAI U.S. Treasury Bond Index Fund Fidelity® SAI U.S. Treasury Bond Index Fund : FUTBX

This semi-annual shareholder report contains information about Fidelity® SAI U.S. Treasury Bond 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 1-800-544-3455 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® SAI U.S. Treasury Bond Index Fund	$ 2	0.03%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$8,971,463,746
Number of Holdings	221
Portfolio Turnover	28%

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

COUPON DISTRIBUTION (% of Fund's net assets)
0.01 - 0.99%	11.5
1 - 1.99%	24.9
2 - 2.99%	16.9
3 - 3.99%	17.1
4 - 4.99%	24.1
5 - 5.99%	0.8
6 - 6.99%	3.6

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 98.9
	Short-Term Investments and Net Other Assets (Liabilities) - 1.1

TOP HOLDINGS (% of Fund's net assets)
US Treasury Notes	75.2
US Treasury Bonds	23.7
	98.9

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 1.9914573.101 2814-TSRS-1025


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® SAI Long-Term Treasury Bond Index Fund Fidelity® SAI Long-Term Treasury Bond Index Fund : FBLTX

This semi-annual shareholder report contains information about Fidelity® SAI Long-Term Treasury Bond 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 1-800-544-3455 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® SAI Long-Term Treasury Bond Index Fund	$ 1	0.03%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$4,209,432,992
Number of Holdings	45
Portfolio Turnover	35%

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

COUPON DISTRIBUTION (% of Fund's net assets)
1 - 1.99%	9.6
2 - 2.99%	30.1
3 - 3.99%	24.2
4 - 4.99%	35.3

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 99.2
	Short-Term Investments and Net Other Assets (Liabilities) - 0.8

TOP HOLDINGS (% of Fund's net assets)
US Treasury Bonds	99.2
	99.2

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 1.9914572.101 2801-TSRS-1025


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® Long-Term Treasury Bond Index Fund Fidelity® Long-Term Treasury Bond Index Fund : FNBGX

This semi-annual shareholder report contains information about Fidelity® Long-Term Treasury Bond 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® Long-Term Treasury Bond Index Fund	$ 1	0.03%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$5,015,929,002
Number of Holdings	91
Portfolio Turnover	21%

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

COUPON DISTRIBUTION (% of Fund's net assets)
1 - 1.99%	13.5
2 - 2.99%	19.5
3 - 3.99%	30.4
4 - 4.99%	34.5
5 - 5.99%	1.4

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 99.3
	Short-Term Investments and Net Other Assets (Liabilities) - 0.7

TOP HOLDINGS (% of Fund's net assets)
US Treasury Bonds	98.6
US Treasury Notes	0.7
	99.3

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 1.9914567.101 3047-TSRS-1025


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® Intermediate Treasury Bond Index Fund Fidelity® Intermediate Treasury Bond Index Fund : FUAMX

This semi-annual shareholder report contains information about Fidelity® Intermediate Treasury Bond 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® Intermediate Treasury Bond Index Fund	$ 2	0.03%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$6,824,870,782
Number of Holdings	45
Portfolio Turnover	45%

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

COUPON DISTRIBUTION (% of Fund's net assets)
0.01 - 0.99%	4.5
1 - 1.99%	13.5
2 - 2.99%	6.8
3 - 3.99%	14.4
4 - 4.99%	59.9
6 - 6.99%	0.2

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 99.3
	Short-Term Investments and Net Other Assets (Liabilities) - 0.7

TOP HOLDINGS (% of Fund's net assets)
US Treasury Notes	99.1
US Treasury Bonds	0.2
	99.3

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 1.9914566.101 3045-TSRS-1025


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® SAI Intermediate Treasury Bond Index Fund Fidelity® SAI Intermediate Treasury Bond Index Fund : FSIWX

This semi-annual shareholder report contains information about Fidelity® SAI Intermediate Treasury Bond 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 1-800-544-3455 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® SAI Intermediate Treasury Bond Index Fund	$ 2	0.03%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$3,793,942,607
Number of Holdings	48
Portfolio Turnover	53%

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

COUPON DISTRIBUTION (% of Fund's net assets)
0.01 - 0.99%	3.0
1 - 1.99%	14.5
2 - 2.99%	5.8
3 - 3.99%	15.8
4 - 4.99%	60.0
5 - 5.99%	0.0
6 - 6.99%	0.1

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 99.2
	Short-Term Investments and Net Other Assets (Liabilities) - 0.8

TOP HOLDINGS (% of Fund's net assets)
US Treasury Notes	99.1
US Treasury Bonds	0.1
	99.2

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 1.9916272.100 7703-TSRS-1025


	SEMI-ANNUAL SHAREHOLDER REPORT \| AS OF AUGUST 31, 2025
	Fidelity® SAI Short-Term Treasury Bond Index Fund Fidelity® SAI Short-Term Treasury Bond Index Fund : FSSWX

This semi-annual shareholder report contains information about Fidelity® SAI Short-Term Treasury Bond 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 1-800-544-3455 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® SAI Short-Term Treasury Bond Index Fund	$ 2	0.03%

Key Fund Statistics

(as of August 31, 2025)

KEY FACTS
Fund Size	$362,276,603
Number of Holdings	111
Portfolio Turnover	82%

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

COUPON DISTRIBUTION (% of Fund's net assets)
0.01 - 0.99%	4.6
1 - 1.99%	5.7
2 - 2.99%	3.1
3 - 3.99%	51.0
4 - 4.99%	34.0
5 - 5.99%	0.1
6 - 6.99%	0.3

ASSET ALLOCATION (% of Fund's net assets)

	U.S. Treasury Obligations - 98.8
	Short-Term Investments and Net Other Assets (Liabilities) - 1.2

TOP HOLDINGS (% of Fund's net assets)
US Treasury Notes	98.4
US Treasury Bonds	0.4
	98.8

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 1.9916277.100 7700-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® Series Long-Term Treasury Bond 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® Series Long-Term Treasury Bond 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.

"BLOOMBERG ®" and the Bloomberg indices listed herein (the "Indices") are service marks of Bloomberg Finance L.P. and its affiliates, including Bloomberg Index Services Limited ("BISL"), the administrator of the Indices (collectively, "Bloomberg") and have been licensed for use for certain purposes by Fidelity. Bloomberg is not affiliated with Fidelity, and Bloomberg does not approve, endorse, review, or recommend the fund. Bloomberg does not guarantee the timeliness, accuracy, or completeness of any data or information relating to the fund.

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® Series Long-Term Treasury Bond Index Fund

Schedule of Investments August 31, 2025 (Unaudited)

Showing Percentage of Net Assets

U.S. Treasury Obligations - 99.1%
	Yield (%) (a)	Principal Amount (b)	Value ($)
US Treasury Bonds 1.125% 5/15/2040	4.69 to 4.88	74,617,000	46,434,508
US Treasury Bonds 1.25% 5/15/2050	4.88	56,000,000	26,387,812
US Treasury Bonds 1.375% 11/15/2040	2.02 to 3.49	399,563,000	254,643,374
US Treasury Bonds 1.375% 8/15/2050	4.97 to 5.03	105,500,000	50,969,688
US Treasury Bonds 1.625% 11/15/2050	4.92 to 5.04	523,600,000	270,144,875
US Treasury Bonds 1.75% 8/15/2041	1.97 to 4.77	296,740,000	196,567,069
US Treasury Bonds 1.875% 11/15/2051	3.11 to 4.80	353,820,000	192,555,478
US Treasury Bonds 1.875% 2/15/2041	1.92 to 4.40	633,606,000	435,430,872
US Treasury Bonds 1.875% 2/15/2051	2.12 to 4.79	611,705,000	336,509,436
US Treasury Bonds 2% 11/15/2041	1.83 to 4.09	915,080,000	627,437,468
US Treasury Bonds 2% 2/15/2050	1.64 to 4.99	435,249,000	251,254,284
US Treasury Bonds 2% 8/15/2051	1.90 to 4.92	835,220,000	471,377,288
US Treasury Bonds 2.25% 2/15/2052	2.17 to 5.04	1,428,240,000	853,763,938
US Treasury Bonds 2.25% 5/15/2041	1.83 to 4.45	831,582,000	602,604,599
US Treasury Bonds 2.25% 8/15/2046	3.02 to 5.04	185,341,000	120,080,695
US Treasury Bonds 2.25% 8/15/2049	2.55 to 4.83	240,147,000	148,196,966
US Treasury Bonds 2.375% 11/15/2049	4.26 to 4.94	361,492,000	228,784,896
US Treasury Bonds 2.375% 2/15/2042	2.60 to 3.32	864,460,000	625,140,560
US Treasury Bonds 2.375% 5/15/2051	1.90 to 5.08	651,374,000	404,742,432
US Treasury Bonds 2.5% 2/15/2045	2.99 to 4.23	686,749,000	478,470,905
US Treasury Bonds 2.5% 2/15/2046	3.02 to 4.87	186,618,000	127,971,836
US Treasury Bonds 2.5% 5/15/2046	3.02 to 3.43	136,970,000	93,642,537
US Treasury Bonds 2.75% 11/15/2042	1.48 to 4.32	193,274,000	146,080,415
US Treasury Bonds 2.75% 11/15/2047	3.06 to 4.90	267,357,000	187,745,186
US Treasury Bonds 2.75% 8/15/2042	3.01 to 4.15	252,260,000	191,638,769
US Treasury Bonds 2.75% 8/15/2047	2.39 to 3.20	458,264,000	322,771,805
US Treasury Bonds 2.875% 11/15/2046	3.06 to 4.65	11,125,000	8,100,390
US Treasury Bonds 2.875% 5/15/2043	2.31 to 4.03	241,482,000	184,677,131
US Treasury Bonds 2.875% 5/15/2049	1.40 to 4.92	596,099,000	421,530,478
US Treasury Bonds 2.875% 5/15/2052	3.02 to 4.96	269,780,000	186,032,278
US Treasury Bonds 2.875% 8/15/2045	3.36 to 4.04	18,732,000	13,852,167
US Treasury Bonds 3% 11/15/2044	2.99 to 3.82	172,537,000	131,633,600
US Treasury Bonds 3% 11/15/2045	1.74 to 4.48	381,862,000	287,947,814
US Treasury Bonds 3% 2/15/2047	1.89 to 3.13	489,794,000	363,825,106
US Treasury Bonds 3% 2/15/2048	1.43 to 3.88	595,209,000	436,618,353
US Treasury Bonds 3% 2/15/2049	4.13 to 4.90	376,287,000	273,322,531
US Treasury Bonds 3% 5/15/2042	3.14 to 4.13	79,079,000	62,725,710
US Treasury Bonds 3% 5/15/2045	2.33 to 4.02	158,044,000	119,817,108
US Treasury Bonds 3% 5/15/2047	1.92 to 4.50	234,862,000	173,917,145
US Treasury Bonds 3% 8/15/2048	2.39 to 4.52	203,982,000	148,859,051
US Treasury Bonds 3% 8/15/2052	3.29 to 5.04	470,480,000	332,717,575
US Treasury Bonds 3.125% 11/15/2041	1.92 to 3.03	59,163,000	48,229,400
US Treasury Bonds 3.125% 2/15/2042	2.65 to 3.99	154,840,000	125,583,708
US Treasury Bonds 3.125% 2/15/2043	3.01 to 5.01	140,221,000	111,831,725
US Treasury Bonds 3.125% 5/15/2048	1.51 to 4.93	273,142,000	204,525,741
US Treasury Bonds 3.125% 8/15/2044	1.96 to 4.20	77,966,000	60,929,211
US Treasury Bonds 3.25% 5/15/2042	3.27 to 4.64	329,100,000	270,620,473
US Treasury Bonds 3.375% 11/15/2048	3.70 to 5.19	310,991,000	242,682,312
US Treasury Bonds 3.375% 5/15/2044	2.95 to 3.01	122,930,000	100,163,941
US Treasury Bonds 3.375% 8/15/2042	4.41 to 5.15	262,860,000	219,241,669
US Treasury Bonds 3.5% 2/15/2039	3.03 to 3.84	78,034,000	70,361,673
US Treasury Bonds 3.625% 2/15/2044	1.64 to 3.82	142,857,000	121,171,753
US Treasury Bonds 3.625% 2/15/2053	3.67 to 5.08	342,780,000	274,371,289
US Treasury Bonds 3.625% 5/15/2053	3.84 to 4.00	741,700,000	593,041,299
US Treasury Bonds 3.625% 8/15/2043	1.23 to 5.02	393,132,000	335,298,595
US Treasury Bonds 3.75% 11/15/2043	3.04 to 4.82	103,069,000	89,239,234
US Treasury Bonds 3.75% 8/15/2041	2.19 to 4.60	107,358,000	95,682,818
US Treasury Bonds 3.875% 2/15/2043	4.71 to 4.92	184,400,000	163,849,485
US Treasury Bonds 3.875% 5/15/2043	4.73 to 5.28	236,000,000	209,095,080
US Treasury Bonds 3.875% 8/15/2040	4.78	189,600,000	173,669,156
US Treasury Bonds 4% 11/15/2042	3.96 to 5.22	251,320,000	227,670,396
US Treasury Bonds 4% 11/15/2052	3.60 to 4.81	387,400,000	332,467,889
US Treasury Bonds 4.125% 8/15/2044	4.60 to 4.80	92,400,000	83,936,016
US Treasury Bonds 4.125% 8/15/2053	4.70 to 5.07	482,900,000	422,933,628
US Treasury Bonds 4.25% 11/15/2040	2.93 to 3.12	47,867,000	45,671,848
US Treasury Bonds 4.25% 2/15/2054	4.37 to 4.99	233,000,000	208,462,188
US Treasury Bonds 4.25% 5/15/2039	3.03 to 4.73	13,257,000	12,874,307
US Treasury Bonds 4.25% 8/15/2054	4.13 to 4.72	522,300,000	467,295,281
US Treasury Bonds 4.375% 11/15/2039	4.63 to 4.83	146,400,000	143,008,782
US Treasury Bonds 4.375% 2/15/2038	2.35 to 4.41	57,424,000	57,275,954
US Treasury Bonds 4.375% 5/15/2040	4.06 to 4.75	114,924,900	111,818,336
US Treasury Bonds 4.375% 5/15/2041	2.99 to 4.79	104,568,000	100,806,003
US Treasury Bonds 4.375% 8/15/2043	4.39 to 4.72	88,670,000	83,841,642
US Treasury Bonds 4.5% 11/15/2054	4.37 to 4.80	604,100,000	563,913,190
US Treasury Bonds 4.5% 2/15/2036	1.69 to 4.51	97,818,000	100,324,586
US Treasury Bonds 4.5% 2/15/2044	4.74 to 4.92	450,900,000	432,194,693
US Treasury Bonds 4.5% 5/15/2038	3.97 to 4.79	62,700,000	63,346,594
US Treasury Bonds 4.5% 8/15/2039	4.14	48,244,000	47,901,015
US Treasury Bonds 4.625% 11/15/2044	4.47 to 4.86	219,100,000	212,544,116
US Treasury Bonds 4.625% 2/15/2040	4.62 to 4.85	30,743,000	30,793,437
US Treasury Bonds 4.625% 2/15/2055	4.47 to 4.92	668,900,000	637,545,313
US Treasury Bonds 4.625% 5/15/2044	4.74 to 4.75	341,000,000	331,702,424
US Treasury Bonds 4.625% 5/15/2054	4.34 to 4.80	473,400,000	451,005,960
US Treasury Bonds 4.75% 11/15/2043	4.52 to 4.90	383,000,000	379,454,259
US Treasury Bonds 4.75% 11/15/2053	4.21 to 4.82	757,200,000	736,081,223
US Treasury Bonds 4.75% 2/15/2037	2.93 to 2.95	28,863,000	30,032,176
US Treasury Bonds 4.75% 2/15/2041	3.79 to 4.87	235,771,100	237,668,322
US Treasury Bonds 4.75% 5/15/2055	4.79 to 4.89	364,300,000	354,395,594
US Treasury Bonds 4.75% 8/15/2045	4.74	37,700,000	37,741,233
US Treasury Bonds 4.75% 8/15/2055	4.92	167,500,000	162,998,438
US Treasury Bonds 5% 5/15/2037	1.70 to 4.41	136,927,000	145,484,938
US Treasury Bonds 5% 5/15/2045	4.79 to 4.89	90,000,000	91,504,688
US Treasury Notes 4.75% 2/15/2045	4.71 to 4.94	213,400,000	210,232,343
TOTAL U.S. TREASURY OBLIGATIONS (Cost $26,649,020,110)			21,901,439,502

Money Market Funds - 1.3%
	Yield (%)	Shares	Value ($)
Fidelity Cash Central Fund (c) (Cost $286,045,696)	4.36	285,988,498	286,045,696

TOTAL INVESTMENT IN SECURITIES - 100.4% (Cost $26,935,065,806)	22,187,485,198
NET OTHER ASSETS (LIABILITIES) - (0.4)%	(94,768,695)
NET ASSETS - 100.0%	22,092,716,503

Legend

(a)	Yield represents either the annualized yield at the date of purchase, or the stated coupon rate, or, for floating and adjustable rate securities, the rate at period end.

(b)	Amount is stated in United States dollars unless otherwise noted.

(c)

Affiliated fund that is generally available only to investment companies and other accounts managed by Fidelity Investments. The rate quoted is the annualized seven-day yield of the fund at period end. A complete unaudited listing of the fund's holdings as of its most recent quarter end is available upon request. In addition, each Fidelity Central Fund's financial statements are available on the SEC's website or upon request.

Affiliated Central Funds

Fiscal year to date information regarding the Fund's investments in Fidelity Central Funds, including the ownership percentage, is presented below.

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	% ownership, end of period
Fidelity Cash Central Fund	253,067,874	872,353,228	839,375,406	1,948,495	-	-	286,045,696	285,988,498	0.5%
Fidelity Securities Lending Cash Central Fund	222,273,265	127,276,450	349,549,715	7,881	-	-	-	-	0.0%
Total	475,341,139	999,629,678	1,188,925,121	1,956,376	-	-	286,045,696

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 in the dividend income column for Fidelity Securities Lending Cash Central Fund represents the income earned on investing cash collateral, less rebates paid to borrowers and any lending agent fees associated with the loan, plus any premium income received for lending certain types of securities.

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:

U.S. Treasury Obligations	21,901,439,502	-	21,901,439,502	-

Money Market Funds	286,045,696	286,045,696	-	-
Total Investments in Securities:	22,187,485,198	286,045,696	21,901,439,502	-

Financial Statements (Unaudited)

Statement of Assets and Liabilities
As of August 31, 2025 (Unaudited)
Assets
Investment in securities, at value - See accompanying schedule:
Unaffiliated issuers (cost $26,649,020,110)	$	21,901,439,502
Fidelity Central Funds (cost $286,045,696)		286,045,696


Total Investment in Securities (cost $26,935,065,806)			$	22,187,485,198
Receivable for investments sold				126,968,125
Receivable for fund shares sold				131,358,886
Interest receivable				152,678,803
Distributions receivable from Fidelity Central Funds				582,390
Total assets				22,599,073,402
Liabilities
Payable for investments purchased	$	200,771,734
Payable for fund shares redeemed		305,542,026
Distributions payable		3,665
Other payables and accrued expenses		39,474
Total liabilities				506,356,899
Net Assets			$	22,092,716,503
Net Assets consist of:
Paid in capital			$	29,187,929,867
Total accumulated earnings (loss)				(7,095,213,364)
Net Assets			$	22,092,716,503
Net Asset Value, offering price and redemption price per share ($22,092,716,503 ÷ 4,157,118,756 shares)			$	5.31

Statement of Operations
Six months ended August 31, 2025 (Unaudited)
Investment Income
Interest			$	439,704,368
Income from Fidelity Central Funds (including $7,881 from security lending)				1,956,376
Total income				441,660,744
Expenses
Custodian fees and expenses	$	74,886
Independent trustees' fees and expenses		23,928
Total expenses before reductions		98,814
Expense reductions		(22)
Total expenses after reductions				98,792
Net Investment income (loss)				441,561,952
Realized and Unrealized Gain (Loss)
Net realized gain (loss) on:
Investment Securities:
Unaffiliated issuers		(384,712,869)
Total net realized gain (loss)				(384,712,869)
Change in net unrealized appreciation (depreciation) on investment securities				(648,443,640)
Net gain (loss)				(1,033,156,509)
Net increase (decrease) in net assets resulting from operations			$	(591,594,557)

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)	$	441,561,952	$	729,606,577
Net realized gain (loss)		(384,712,869)		(913,871,107)
Change in net unrealized appreciation (depreciation)		(648,443,640)		950,687,866
Net increase (decrease) in net assets resulting from operations		(591,594,557)		766,423,336
Distributions to shareholders		(408,346,129)		(676,666,979)

Share transactions
Proceeds from sales of shares		3,182,844,602		5,495,827,183
Reinvestment of distributions		408,346,128		676,584,575
Cost of shares redeemed		(1,541,838,023)		(4,982,406,014)

Net increase (decrease) in net assets resulting from share transactions		2,049,352,707		1,190,005,744
Total increase (decrease) in net assets		1,049,412,021		1,279,762,101

Net Assets
Beginning of period		21,043,304,482		19,763,542,381
End of period	$	22,092,716,503	$	21,043,304,482

Other Information
Shares
Sold		598,776,356		1,006,501,340
Issued in reinvestment of distributions		76,053,029		122,142,333
Redeemed		(286,577,023)		(895,144,557)
Net increase (decrease)		388,252,362		233,499,116

Financial Highlights

Fidelity® Series Long-Term Treasury Bond 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	$	5.58	$	5.59	$	5.94	$	8.05	$	8.33	$	10.06
Income from Investment Operations
Net investment income (loss) B,C		.112		.213		.202		.185		.175		.201
Net realized and unrealized gain (loss)		(.278)		(.026) D		(.365)		(2.121)		(.253)		(.752)
Total from investment operations		(.166)		.187		(.163)		(1.936)		(.078)		(.551)
Distributions from net investment income		(.104)		(.197)		(.187)		(.174)		(.169)		(.199)
Distributions from net realized gain		-		-		-		-		(.033)		(.980)
Total distributions		(.104)		(.197)		(.187)		(.174)		(.202)		(1.179)
Net asset value, end of period	$	5.31	$	5.58	$	5.59	$	5.94	$	8.05	$	8.33
Total Return E,F		(2.98) %		3.44%		(2.77)%		(24.16)%		(1.01)%		(6.47)%
Ratios to Average Net Assets C,G,H
Expenses before reductions I		-% J		-%		-%		-%		-%		-%
Expenses net of fee waivers, if any I		- % J		-%		-%		-%		-%		-%
Expenses net of all reductions, if any I		-% J		-%		-%		-%		-%		-%
Net investment income (loss)		4.17% J		3.84%		3.53%		2.87%		2.10%		2.03%
Supplemental Data
Net assets, end of period (000 omitted)	$	22,092,717	$	21,043,304	$	19,763,542	$	17,545,738	$	15,129,018	$	9,356,431
Portfolio turnover rate K		10 % J		18%		11%		10%		18%		56%

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.

DThe amount shown for a share outstanding does not correspond with the aggregate net gain (loss) on investments for the period due to the timing of sales and repurchases of shares in relation to fluctuating market values of the investments of the Fund.

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. For additional expense information related to investments in Fidelity Central Funds, please refer to the "Investments in Fidelity Central Funds" note found in the Notes to Financial Statements section of the most recent Annual or Semi-Annual report.

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.

IAmount represents less than .005%.

JAnnualized.

KAmount 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 Series Long-Term Treasury Bond Index Fund (the Fund) is a fund of Fidelity Salem Street Trust (the Trust) and is authorized to issue an unlimited number of shares. Shares are offered only to certain other Fidelity funds, Fidelity managed 529 plans, and Fidelity managed collective investment trusts. 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 Massachusetts business trust.

2. Investments in Fidelity Central Funds.

Funds may invest in Fidelity Central Funds, which are open-end investment companies generally available only to other investment companies and accounts managed by the investment adviser and its affiliates. The Schedule of Investments lists any Fidelity Central Funds held as an investment as of period end, but does not include the underlying holdings of each Fidelity Central Fund. An investing fund indirectly bears its proportionate share of the expenses of the underlying Fidelity Central Funds.

Based on its investment objective, each Fidelity Central Fund may invest or participate in various investment vehicles or strategies that are similar to those of the investing fund. These strategies are consistent with the investment objectives of the investing fund and may involve certain economic risks which may cause a decline in value of each of the Fidelity Central Funds and thus a decline in the value of the investing fund.

Fidelity Central Fund	Investment Manager	Investment Objective	Investment Practices	Expense RatioA
Fidelity Money Market Central Funds	Fidelity Management & Research Company LLC (FMR)	Each fund seeks to obtain a high level of current income consistent with the preservation of capital and liquidity.	Short-term Investments	Less than .005%

A Expenses expressed as a percentage of average net assets and are as of each underlying Central Fund's most recent annual or semi-annual shareholder report.

A complete unaudited list of holdings for each Fidelity Central Fund is available upon request or at the Securities and Exchange Commission website at www.sec.gov. In addition, the financial statements of the Fidelity Central Funds which contain the significant accounting policies (including investment valuation policies) of those funds, and are not covered by the Report of Independent Registered Public Accounting Firm, are available on the Securities and Exchange Commission website or upon request.

3. 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 Board of Trustees (the Board) has designated the Fund's investment adviser as the valuation designee responsible for the fair valuation function and performing fair value determinations as needed. The investment adviser has established a Fair Value Committee (the Committee) to carry out the day-to-day fair valuation responsibilities and has adopted policies and procedures to govern the fair valuation process and the activities of the Committee. In accordance with these fair valuation policies and procedures, which have been approved by the Board, the Fund attempts to obtain prices from one or more third party pricing services or brokers to value its investments. When current market prices, quotations or currency exchange rates are not readily available or reliable, investments will be fair valued in good faith by the Committee, in accordance with the policies and procedures. Factors used in determining fair value vary by investment type and may include market or investment specific events, transaction data, estimated cash flows, and market observations of comparable investments. The frequency that the fair valuation procedures are used cannot be predicted and they may be utilized to a significant extent. The Committee manages the Fund's fair valuation practices and maintains the fair valuation policies and procedures. The Fund's investment adviser reports to the Board information regarding the fair valuation process and related material matters.

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:

Debt securities, including restricted securities, are valued based on evaluated prices received from third party pricing services or from brokers who make markets in such securities. U.S. government and government agency obligations are valued by pricing services who utilize matrix pricing which considers yield or price of bonds of comparable quality, coupon, maturity and type or by broker-supplied prices. When independent prices are unavailable or unreliable, debt securities may be valued utilizing pricing methodologies which consider similar factors that would be used by third party pricing services. Debt securities are generally categorized as Level 2 in the hierarchy but may be Level 3 depending on the circumstances.

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

Changes in valuation techniques may result in transfers in or out of an assigned level within the disclosure hierarchy. The aggregate value of investments by input level as of August 31, 2025 is included at the end of the Fund's Schedule of Investments.

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 Fidelity Central Funds, if any, are recorded on the ex-dividend date. Interest income is accrued as earned and includes coupon interest and amortization of premium and accretion of discount on debt securities as applicable.

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 daily and paid monthly from net investment income. Distributions from realized gains, if any, 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 market discount, capital loss carryforwards and 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	$35,650,395
Gross unrealized depreciation	(4,709,293,044)
Net unrealized appreciation (depreciation)	$(4,673,642,649)
Tax cost	$26,861,127,847

Capital loss carryforwards are only available to offset future capital gains of the Fund to the extent provided by regulations and may be limited. The capital loss carryforward information presented below, including any applicable limitation, is estimated as of prior fiscal period end and is subject to adjustment.

Short-term	$(188,109,629)
Long-term	(1,853,727,588)
Total capital loss carryforward	$(2,041,837,217)

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.

4. Fees and Other Transactions with Affiliates.

Management Fee. Fidelity Management & Research Company LLC (the investment adviser) and its affiliates provide the Fund with investment management related services for which the Fund does not pay a management fee. Under the management contract, the investment adviser or an affiliate pays all ordinary operating expenses of the Fund, except custody fees, fees and expenses of the independent Trustees, and certain miscellaneous expenses such as proxy and shareholder meeting expenses.

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. Committed Line of Credit.

Certain Funds participate with other funds managed by the investment adviser or an affiliate in a $4.25 billion credit facility (the "line of credit") to be utilized for temporary or emergency purposes to fund shareholder redemptions or for other short-term liquidity purposes.

Commitment fees are charged based on the unused amount of the line of credit at an annual rate of .10%, and then allocated to each participating fund based on its pro-rata portion of the line of credit. The commitment fees are borne by the investment adviser.

Interest is charged to a participating fund based on its borrowings at an annual rate of .75% plus the highest of (i) daily SOFR plus a .10% spread adjustment, (ii) Federal Funds Effective Rate, or (iii) Overnight Bank Funding Rate. During the period, there were no borrowings on this line of credit.

The line of credit agreement will expire in March 2026 unless extended or renewed.

6. Security Lending.

Funds lend portfolio securities from time to time in order to earn additional income. Lending agents are used, including National Financial Services (NFS), an affiliate of the investment adviser. Pursuant to a securities lending agreement, NFS will receive a fee, which is capped at 9.9% of a fund's daily lending revenue, for its services as lending agent. A fund may lend securities to certain qualified borrowers, including NFS. On the settlement date of the loan, the borrowers provide collateral (in the form of U.S. Treasury obligations, letters of credit and/or cash) against the loaned securities and maintains collateral in an amount not less than 100% of the fair value of the loaned securities during the period of the loan. The fair value of the loaned securities is determined at the close of business of a fund and any additional required collateral is delivered to a fund on the next business day. A fund or borrower may terminate the loan at any time, and if the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund may apply collateral received from the borrower against the obligation. A fund may experience delays and costs in recovering the securities loaned or gaining access to non-cash collateral. Any cash collateral received is invested in the Fidelity Securities Lending Cash Central Fund. Any loaned securities are identified as such in the Schedule of Investments, and the value of loaned securities and cash collateral at period end, as applicable, are presented in the Statement of Assets and Liabilities. Security lending income represents the income earned on investing cash collateral less rebates paid to borrowers, plus any premium income received, or for non-cash collateral, fees received from borrowers as compensation for the securities loaned. Securities lending income is reduced by any lending agent fees associated with the loan. Any security lending income earned on investing cash collateral is presented in the Statement of Operations as a component of income from Fidelity Central Funds. Any security lending income earned on non-cash collateral is presented in the Statement of Operations as a component of interest. Affiliated security lending activity, if any, was as follows:

	Total Security Lending Fees Paid to NFS ($)	Security Lending Income From Securities Loaned to NFS ($)	Value of Securities Loaned to NFS at Period End ($)
Fidelity Series Long-Term Treasury Bond Index Fund	837	-	-

7. Expense Reductions.

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 $22.

8. 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.

At the end of the period, mutual funds and accounts managed by the investment adviser or its affiliates were the owners of record of all of the outstanding shares of the Fund.

9. 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.

1.9872675.109

XS8-SANN-1025

Fidelity® SAI U.S. Treasury Bond Index Fund

Semi-Annual Report

August 31, 2025

Offered exclusively to certain clients of the Adviser, or its affiliates, including Strategic Advisers LLC (Strategic Advisers) - not available for sale to the general public. Fidelity® SAI is a product name of Fidelity® funds dedicated to certain programs affiliated with Strategic Advisers.

Contents

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

Fidelity® SAI U.S. Treasury Bond 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

You may also call 1-800-544-3455 to request a free copy of the proxy voting guidelines.

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.

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® SAI U.S. Treasury Bond Index Fund

Schedule of Investments August 31, 2025 (Unaudited)

Showing Percentage of Net Assets

U.S. Treasury Obligations - 98.9%
	Yield (%) (a)	Principal Amount (b)	Value ($)
US Treasury Bonds 1.125% 5/15/2040	3.41 to 3.46	15,484,000	9,635,766
US Treasury Bonds 1.125% 8/15/2040	2.16 to 3.74	22,637,000	13,935,903
US Treasury Bonds 1.25% 5/15/2050	3.79	72,000	33,927
US Treasury Bonds 1.375% 11/15/2040	2.06 to 2.31	43,434,300	27,680,883
US Treasury Bonds 1.375% 8/15/2050	4.03	4,170,000	2,014,631
US Treasury Bonds 1.625% 11/15/2050	4.41 to 4.70	62,237,500	32,110,660
US Treasury Bonds 1.75% 8/15/2041	2.05 to 3.46	89,327,000	59,172,159
US Treasury Bonds 1.875% 11/15/2051	2.50 to 4.41	83,063,000	45,204,442
US Treasury Bonds 1.875% 2/15/2041	2.27	14,329,000	9,847,269
US Treasury Bonds 1.875% 2/15/2051	2.30 to 4.40	110,431,000	60,749,991
US Treasury Bonds 2% 11/15/2041	2.14 to 3.45	83,700,000	57,390,082
US Treasury Bonds 2% 2/15/2050	3.51 to 3.79	30,778,000	17,767,081
US Treasury Bonds 2% 8/15/2051	3.23 to 4.83	76,045,000	42,917,897
US Treasury Bonds 2.25% 2/15/2052	3.02 to 3.93	56,800,000	33,953,531
US Treasury Bonds 2.25% 5/15/2041	2.18 to 3.39	67,333,000	48,792,753
US Treasury Bonds 2.25% 8/15/2046	3.41	1,600,000	1,036,625
US Treasury Bonds 2.25% 8/15/2049	3.53	80,000	49,369
US Treasury Bonds 2.375% 2/15/2042	3.24	32,900,000	23,791,875
US Treasury Bonds 2.375% 5/15/2051	3.98 to 4.54	100,837,000	62,656,803
US Treasury Bonds 2.5% 2/15/2045	4.15	2,401,000	1,672,822
US Treasury Bonds 2.5% 2/15/2046	3.09 to 4.13	15,623,000	10,713,350
US Treasury Bonds 2.5% 5/15/2046	2.98 to 4.81	24,683,000	16,875,073
US Treasury Bonds 2.75% 11/15/2042	4.05	13,826,000	10,449,972
US Treasury Bonds 2.75% 11/15/2047	3.09	318,000	223,308
US Treasury Bonds 2.75% 8/15/2042	3.26 to 4.84	59,738,000	45,382,212
US Treasury Bonds 2.75% 8/15/2047	3.10 to 3.25	5,231,000	3,684,381
US Treasury Bonds 2.875% 11/15/2046	3.05 to 4.61	5,289,000	3,851,053
US Treasury Bonds 2.875% 5/15/2043	3.02 to 4.08	50,784,000	38,837,857
US Treasury Bonds 2.875% 5/15/2049	4.62	11,000	7,779
US Treasury Bonds 2.875% 5/15/2052	3.20 to 4.87	12,400,000	8,550,672
US Treasury Bonds 2.875% 8/15/2045	1.43 to 4.94	58,254,000	43,078,378
US Treasury Bonds 3% 11/15/2044	4.13 to 4.76	63,400,000	48,369,742
US Treasury Bonds 3% 11/15/2045	3.71 to 3.99	57,800,000	43,584,813
US Treasury Bonds 3% 2/15/2047	1.70 to 3.41	53,589,000	39,806,579
US Treasury Bonds 3% 2/15/2048	3.07 to 4.97	7,159,000	5,251,518
US Treasury Bonds 3% 2/15/2049	4.59	13,911,000	10,104,494
US Treasury Bonds 3% 5/15/2042	3.25 to 4.92	14,138,000	11,214,306
US Treasury Bonds 3% 5/15/2045	2.40 to 3.83	39,700,000	30,097,563
US Treasury Bonds 3% 5/15/2047	3.38 to 3.41	69,492,000	51,459,369
US Treasury Bonds 3% 8/15/2048	3.80 to 4.55	13,608,000	9,930,651
US Treasury Bonds 3% 8/15/2052	3.02 to 4.67	100,400,000	71,001,625
US Treasury Bonds 3.125% 11/15/2041	3.41 to 4.15	50,864,000	41,464,094
US Treasury Bonds 3.125% 2/15/2042	3.99 to 4.49	12,800,000	10,381,500
US Treasury Bonds 3.125% 2/15/2043	4.54	27,201,000	21,693,860
US Treasury Bonds 3.125% 5/15/2048	4.05	4,500	3,370
US Treasury Bonds 3.375% 11/15/2048	3.13	1,791,300	1,397,844
US Treasury Bonds 3.375% 5/15/2044	3.50 to 4.46	61,800,000	50,354,930
US Treasury Bonds 3.375% 8/15/2042	4.93	10,700,000	8,924,469
US Treasury Bonds 3.5% 2/15/2039	2.66	315,000	284,029
US Treasury Bonds 3.625% 2/15/2044	3.85 to 4.56	10,956,000	9,292,913
US Treasury Bonds 3.625% 2/15/2053	3.66 to 4.71	59,000,000	47,225,352
US Treasury Bonds 3.625% 5/15/2053	4.25 to 4.54	13,900,000	11,114,027
US Treasury Bonds 3.625% 8/15/2043	3.59 to 4.55	42,601,000	36,333,993
US Treasury Bonds 3.875% 5/15/2043	4.78	8,400,000	7,442,367
US Treasury Bonds 4% 11/15/2052	4.40	41,900,000	35,958,711
US Treasury Bonds 4.125% 8/15/2053	4.20 to 5.07	91,100,000	79,787,230
US Treasury Bonds 4.25% 11/15/2040	3.71	80,000	76,331
US Treasury Bonds 4.25% 2/15/2054	4.44 to 4.51	43,600,000	39,008,375
US Treasury Bonds 4.25% 5/15/2039	3.45 to 3.99	1,598,000	1,551,870
US Treasury Bonds 4.375% 11/15/2039	4.37	340,000	332,124
US Treasury Bonds 4.375% 2/15/2038	2.80 to 3.16	6,284,000	6,267,799
US Treasury Bonds 4.375% 5/15/2041	3.28 to 3.79	7,517,000	7,246,564
US Treasury Bonds 4.5% 11/15/2054	4.37 to 4.80	31,000,000	28,937,773
US Treasury Bonds 4.5% 2/15/2036	2.61 to 3.34	24,732,200	25,365,963
US Treasury Bonds 4.5% 2/15/2044	4.68	10,900,000	10,447,820
US Treasury Bonds 4.5% 5/15/2038	4.16	24,300,000	24,550,594
US Treasury Bonds 4.5% 8/15/2039	4.39	14,731,000	14,626,272
US Treasury Bonds 4.625% 2/15/2040	2.99	5,000	5,008
US Treasury Bonds 4.625% 2/15/2055	4.58 to 4.92	50,900,000	48,514,063
US Treasury Bonds 4.625% 5/15/2054	4.54 to 4.63	22,100,000	21,054,566
US Treasury Bonds 4.75% 11/15/2053	4.00 to 4.48	37,400,000	36,356,891
US Treasury Bonds 4.75% 2/15/2037	2.32 to 2.78	13,000	13,527
US Treasury Bonds 4.75% 2/15/2041	4.03	11,100,000	11,189,320
US Treasury Bonds 4.75% 5/15/2055	4.79 to 4.89	30,700,000	29,865,344
US Treasury Bonds 4.75% 8/15/2045	4.74	8,000,000	8,008,750
US Treasury Bonds 4.75% 8/15/2055	4.91 to 4.92	19,900,000	19,365,188
US Treasury Bonds 5% 5/15/2037	2.90 to 4.31	4,967,000	5,277,438
US Treasury Bonds 5% 5/15/2045	4.85 to 4.92	13,500,000	13,725,703
US Treasury Bonds 5.25% 11/15/2028	2.65 to 2.98	31,601,000	33,151,424
US Treasury Bonds 5.25% 2/15/2029	2.75 to 3.84	10,374,000	10,951,864
US Treasury Bonds 6.125% 11/15/2027	2.86 to 2.94	139,604,000	147,080,450
US Treasury Bonds 6.25% 5/15/2030	3.95 to 4.21	116,378,000	129,134,120
US Treasury Bonds 6.375% 8/15/2027	3.09 to 3.25	21,500,000	22,618,672
US Treasury Bonds 6.5% 11/15/2026	3.02	39,000	40,365
US Treasury Bonds 6.625% 2/15/2027	2.93 to 3.60	9,550,000	9,970,797
US Treasury Bonds Series 2026, 6.75% 8/15/2026	3.94	2,423,000	2,491,525
US Treasury Notes 0.375% 7/31/2027	0.91 to 3.51	82,414,000	77,501,353
US Treasury Notes 0.375% 9/30/2027	3.68	61,826,000	57,850,781
US Treasury Notes 0.5% 10/31/2027	3.78 to 4.23	119,200,000	111,545,125
US Treasury Notes 0.5% 4/30/2027	1.95 to 4.09	119,444,000	113,387,817
US Treasury Notes 0.5% 5/31/2027	0.55 to 3.64	38,920,000	36,859,976
US Treasury Notes 0.5% 6/30/2027	0.49 to 4.03	25,881,000	24,453,501
US Treasury Notes 0.5% 8/31/2027	1.13 to 2.86	76,109,000	71,572,190
US Treasury Notes 0.625% 11/30/2027	4.18	28,200,700	26,410,617
US Treasury Notes 0.625% 12/31/2027	3.30	15,039,900	14,047,032
US Treasury Notes 0.625% 3/31/2027	0.51	17,704,000	16,878,966
US Treasury Notes 0.625% 5/15/2030	0.80 to 3.52	154,627,000	134,374,487
US Treasury Notes 0.625% 8/15/2030	3.18 to 4.31	129,794,900	111,851,769
US Treasury Notes 0.75% 1/31/2028	0.99 to 1.28	122,528,000	114,525,390
US Treasury Notes 0.875% 11/15/2030	3.02 to 3.72	64,580,900	55,978,523
US Treasury Notes 0.875% 9/30/2026	4.47	62,577,000	60,633,691
US Treasury Notes 1% 7/31/2028	3.07 to 3.92	117,409,000	109,075,713
US Treasury Notes 1.125% 10/31/2026	3.04	107,215,000	103,948,293
US Treasury Notes 1.125% 2/28/2027	3.63 to 4.57	85,938,000	82,735,467
US Treasury Notes 1.125% 2/29/2028	1.28 to 3.05	29,970,000	28,222,140
US Treasury Notes 1.125% 8/31/2028	2.95 to 4.65	129,007,000	120,036,982
US Treasury Notes 1.25% 11/30/2026	1.24 to 3.75	76,047,000	73,718,061
US Treasury Notes 1.25% 12/31/2026	1.61 to 4.30	85,700,000	82,924,793
US Treasury Notes 1.25% 3/31/2028	1.41 to 2.96	39,508,000	37,248,636
US Treasury Notes 1.25% 4/30/2028	3.55 to 4.18	26,499,000	24,941,149
US Treasury Notes 1.25% 5/31/2028	2.94 to 3.62	51,374,000	48,253,431
US Treasury Notes 1.25% 6/30/2028	3.04 to 4.16	147,635,000	138,436,647
US Treasury Notes 1.25% 8/15/2031	1.62 to 4.49	207,366,000	179,185,284
US Treasury Notes 1.25% 9/30/2028	3.65	3,038,000	2,831,986
US Treasury Notes 1.375% 10/31/2028	4.27	30,000,000	28,025,391
US Treasury Notes 1.375% 11/15/2031	3.04 to 3.44	58,246,000	50,330,459
US Treasury Notes 1.375% 12/31/2028	1.56	23,700,000	22,063,219
US Treasury Notes 1.5% 1/31/2027	1.84 to 3.89	65,000,000	63,001,758
US Treasury Notes 1.5% 11/30/2028	3.09	42,500,000	39,792,285
US Treasury Notes 1.5% 2/15/2030	2.99 to 3.64	30,793,000	28,093,801
US Treasury Notes 1.625% 10/31/2026	0.57 to 1.73	87,777,000	85,610,005
US Treasury Notes 1.625% 11/30/2026	1.12	9,625,000	9,374,600
US Treasury Notes 1.625% 5/15/2031	1.39 to 4.41	213,693,000	190,211,813
US Treasury Notes 1.625% 8/15/2029	2.67 to 4.34	121,862,000	113,126,970
US Treasury Notes 1.625% 9/30/2026	3.82 to 4.59	75,600,000	73,848,797
US Treasury Notes 1.75% 1/31/2029	2.00 to 4.20	76,700,000	72,166,910
US Treasury Notes 1.75% 11/15/2029	3.01 to 3.89	21,907,000	20,331,579
US Treasury Notes 1.75% 12/31/2026	3.64	39,400,000	38,381,140
US Treasury Notes 1.875% 2/15/2032	2.90 to 4.34	83,500,000	73,974,479
US Treasury Notes 1.875% 2/28/2027	3.07	28,700,000	27,934,293
US Treasury Notes 1.875% 2/28/2029	3.08	2,900,000	2,736,195
US Treasury Notes 2% 11/15/2026	0.49	30,050,000	29,417,307
US Treasury Notes 2.25% 11/15/2027	4.33	22,300,000	21,661,488
US Treasury Notes 2.25% 2/15/2027	2.40 to 3.18	44,880,000	43,949,091
US Treasury Notes 2.25% 8/15/2027	3.34	15,984,000	15,568,166
US Treasury Notes 2.375% 3/31/2029	4.11 to 4.23	87,300,000	83,702,285
US Treasury Notes 2.375% 4/30/2026	0.46	9,000	8,904
US Treasury Notes 2.375% 5/15/2027	0.55 to 2.98	7,901,000	7,733,104
US Treasury Notes 2.375% 5/15/2029	0.74 to 4.37	162,799,000	155,841,886
US Treasury Notes 2.625% 2/15/2029	1.40 to 2.51	58,844,000	56,982,139
US Treasury Notes 2.625% 7/31/2029	3.56 to 3.75	29,600,000	28,520,062
US Treasury Notes 2.75% 2/15/2028	0.64 to 4.32	91,818,200	90,014,116
US Treasury Notes 2.75% 4/30/2027	2.94	21,100,000	20,785,148
US Treasury Notes 2.75% 5/31/2029	4.52	92,800,000	89,987,000
US Treasury Notes 2.75% 7/31/2027	4.10 to 4.50	30,800,000	30,291,078
US Treasury Notes 2.75% 8/15/2032	3.94 to 4.14	69,000,000	64,064,883
US Treasury Notes 2.875% 4/30/2029	2.88 to 3.49	74,400,000	72,516,750
US Treasury Notes 2.875% 5/15/2028	3.03 to 4.46	52,785,000	51,813,838
US Treasury Notes 2.875% 5/15/2032	3.02 to 4.10	126,700,000	119,008,915
US Treasury Notes 2.875% 8/15/2028	1.28 to 4.00	92,876,000	91,029,364
US Treasury Notes 3.125% 11/15/2028	2.49 to 2.88	26,503,000	26,125,125
US Treasury Notes 3.125% 8/31/2027	4.08	49,400,000	48,927,227
US Treasury Notes 3.125% 8/31/2029	4.48	29,133,900	28,587,639
US Treasury Notes 3.25% 6/30/2027	3.58	73,300,000	72,787,472
US Treasury Notes 3.25% 6/30/2029	3.08	34,300,000	33,837,754
US Treasury Notes 3.375% 5/15/2033	3.96 to 4.91	101,900,000	97,668,761
US Treasury Notes 3.5% 1/31/2030	3.60	47,900,000	47,580,043
US Treasury Notes 3.5% 2/15/2033	3.82 to 4.53	61,800,000	59,902,547
US Treasury Notes 3.625% 3/31/2030	4.31	6,500,000	6,485,781
US Treasury Notes 3.625% 8/15/2028	3.58	40,100,000	40,153,258
US Treasury Notes 3.625% 8/31/2027	3.61	27,100,000	27,105,293
US Treasury Notes 3.625% 8/31/2030	3.69	1,000,000	996,953
US Treasury Notes 3.625% 9/30/2031	4.22	2,000,000	1,977,500
US Treasury Notes 3.75% 6/30/2030	4.08 to 4.26	72,300,000	72,494,871
US Treasury Notes 3.75% 8/15/2027	3.89	81,700,000	81,862,762
US Treasury Notes 3.875% 10/15/2027	4.12	900,000	904,534
US Treasury Notes 3.875% 11/30/2027	4.01	6,500,000	6,536,309
US Treasury Notes 3.875% 11/30/2029	3.99	2,100,000	2,117,883
US Treasury Notes 3.875% 12/31/2029	3.63 to 4.34	22,300,000	22,492,512
US Treasury Notes 3.875% 4/30/2030	3.96	35,600,000	35,901,766
US Treasury Notes 3.875% 7/15/2028	3.89	13,800,000	13,906,734
US Treasury Notes 3.875% 7/31/2027	3.94	54,700,000	54,926,492
US Treasury Notes 3.875% 7/31/2030	3.69 to 3.95	58,700,000	59,172,352
US Treasury Notes 3.875% 8/15/2033	4.03 to 4.57	42,100,000	41,659,266
US Treasury Notes 3.875% 8/15/2034	3.92 to 4.28	83,000,000	81,378,910
US Treasury Notes 3.875% 9/30/2029	4.08	4,900,000	4,943,449
US Treasury Notes 4% 1/15/2027	4.39	76,700,000	76,936,692
US Treasury Notes 4% 1/31/2029	3.90	1,400,000	1,417,555
US Treasury Notes 4% 1/31/2031	4.19 to 4.28	113,000,000	114,341,875
US Treasury Notes 4% 10/31/2029	4.12	11,200,000	11,351,375
US Treasury Notes 4% 2/15/2034	4.24 to 4.69	97,000,000	96,431,640
US Treasury Notes 4% 3/31/2030	3.95	32,700,000	33,148,348
US Treasury Notes 4% 4/30/2032	4.16	32,400,000	32,587,313
US Treasury Notes 4% 5/31/2030	3.78	26,100,000	26,461,934
US Treasury Notes 4% 6/30/2028	4.41	15,400,000	15,572,047
US Treasury Notes 4% 6/30/2032	3.99	29,500,000	29,652,109
US Treasury Notes 4% 7/31/2030	4.05 to 4.35	35,300,000	35,764,691
US Treasury Notes 4% 7/31/2032	3.92 to 4.14	45,800,000	46,007,531
US Treasury Notes 4.125% 10/31/2029	3.70 to 4.15	46,700,000	47,544,613
US Treasury Notes 4.125% 10/31/2031	4.13	5,500,000	5,584,004
US Treasury Notes 4.125% 11/15/2027	3.89 to 4.11	52,900,000	53,462,063
US Treasury Notes 4.125% 11/15/2032	4.32 to 4.34	45,600,000	46,109,438
US Treasury Notes 4.125% 11/30/2029	3.69 to 4.08	64,800,000	65,987,156
US Treasury Notes 4.125% 2/15/2027	4.30	8,700,000	8,745,879
US Treasury Notes 4.125% 2/29/2032	3.92	36,600,000	37,107,539
US Treasury Notes 4.125% 3/31/2029	4.01	30,600,000	31,119,961
US Treasury Notes 4.125% 3/31/2032	4.08	37,700,000	38,208,066
US Treasury Notes 4.125% 9/30/2027	3.56 to 3.83	51,700,000	52,221,039
US Treasury Notes 4.25% 11/15/2034	4.19 to 4.58	75,300,000	75,794,156
US Treasury Notes 4.25% 11/30/2026	4.15	8,120,000	8,163,138
US Treasury Notes 4.25% 12/31/2026	4.25	32,900,000	33,096,629
US Treasury Notes 4.25% 2/15/2028	3.76	42,000,000	42,638,996
US Treasury Notes 4.25% 2/28/2031	4.32	10,600,000	10,855,477
US Treasury Notes 4.25% 5/15/2035	4.23 to 4.39	70,700,000	70,920,938
US Treasury Notes 4.25% 8/15/2035	4.22	25,800,000	25,852,406
US Treasury Notes 4.375% 1/31/2032	4.11 to 4.44	18,500,000	19,017,422
US Treasury Notes 4.375% 11/30/2030	3.87	21,500,000	22,149,199
US Treasury Notes 4.375% 12/15/2026	4.50	32,800,000	33,040,875
US Treasury Notes 4.375% 12/31/2029	4.39	17,600,000	18,098,437
US Treasury Notes 4.375% 5/15/2034	4.34 to 4.49	80,500,000	82,072,266
US Treasury Notes 4.5% 11/15/2033	4.07 to 4.34	74,000,000	76,306,719
US Treasury Notes 4.5% 12/31/2031	4.24 to 4.49	23,100,000	23,917,523
US Treasury Notes 4.5% 5/15/2027	4.68	3,000,000	3,039,961
US Treasury Notes 4.5% 5/31/2029	3.78 to 3.93	66,500,000	68,510,586
US Treasury Notes 4.625% 10/15/2026	4.06	25,700,000	25,922,867
US Treasury Notes 4.625% 2/15/2035	4.16 to 4.21	74,000,000	76,532,191
US Treasury Notes 4.625% 4/30/2029	3.91 to 4.72	50,100,000	51,810,445
US Treasury Notes 4.625% 5/31/2031	4.29	1,200,000	1,250,859
US Treasury Notes 4.625% 9/30/2030	4.33	2,900,000	3,020,758
US Treasury Notes 4.875% 10/31/2030	4.06	26,300,000	27,705,406
TOTAL U.S. TREASURY OBLIGATIONS (Cost $9,211,029,638)			8,869,016,686

Money Market Funds - 0.5%
	Yield (%)	Shares	Value ($)
Fidelity Cash Central Fund (c) (Cost $51,518,105)	4.36	51,507,803	51,518,105

TOTAL INVESTMENT IN SECURITIES - 99.4% (Cost $9,262,547,743)	8,920,534,791
NET OTHER ASSETS (LIABILITIES) - 0.6%	50,928,955
NET ASSETS - 100.0%	8,971,463,746

Legend

(a)	Yield represents either the annualized yield at the date of purchase, or the stated coupon rate, or, for floating and adjustable rate securities, the rate at period end.

(b)	Amount is stated in United States dollars unless otherwise noted.

(c)

Affiliated Central Funds

Fiscal year to date information regarding the Fund's investments in Fidelity Central Funds, including the ownership percentage, is presented below.

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	% ownership, end of period
Fidelity Cash Central Fund	38,080,938	423,409,583	409,972,416	570,847	-	-	51,518,105	51,507,803	0.1%
Fidelity Securities Lending Cash Central Fund	20,724,788	359,564,548	380,289,336	9,145	-	-	-	-	0.0%
Total	58,805,726	782,974,131	790,261,752	579,992	-	-	51,518,105

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

Investment Valuation

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

U.S. Treasury Obligations	8,869,016,686	-	8,869,016,686	-

Money Market Funds	51,518,105	51,518,105	-	-
Total Investments in Securities:	8,920,534,791	51,518,105	8,869,016,686	-

Financial Statements (Unaudited)

Statement of Assets and Liabilities
As of August 31, 2025 (Unaudited)
Assets
Investment in securities, at value - See accompanying schedule:
Unaffiliated issuers (cost $9,211,029,638)	$	8,869,016,686
Fidelity Central Funds (cost $51,518,105)		51,518,105


Total Investment in Securities (cost $9,262,547,743)			$	8,920,534,791
Receivable for investments sold				187,761,095
Receivable for fund shares sold				2,104,817
Interest receivable				53,821,932
Distributions receivable from Fidelity Central Funds				89,872
Prepaid expenses				10,656
Receivable from investment adviser for expense reductions				82,867
Total assets				9,164,406,030
Liabilities
Payable for investments purchased	$	189,032,547
Payable for fund shares redeemed		2,955,898
Distributions payable		607,217
Accrued management fee		296,266
Other payables and accrued expenses		50,356
Total liabilities				192,942,284
Net Assets			$	8,971,463,746
Net Assets consist of:
Paid in capital			$	10,629,816,125
Total accumulated earnings (loss)				(1,658,352,379)
Net Assets			$	8,971,463,746
Net Asset Value, offering price and redemption price per share ($8,971,463,746 ÷ 1,011,969,186 shares)			$	8.87

Statement of Operations
Six months ended August 31, 2025 (Unaudited)
Investment Income
Interest			$	159,858,550
Income from Fidelity Central Funds (including $9,145 from security lending)				579,992
Total income				160,438,542
Expenses
Management fee	$	1,769,039
Custodian fees and expenses		30,131
Independent trustees' fees and expenses		10,376
Registration fees		28,359
Audit fees		30,796
Legal		2,377
Miscellaneous		26,841
Total expenses before reductions		1,897,919
Expense reductions		(549,733)
Total expenses after reductions				1,348,186
Net Investment income (loss)				159,090,356
Realized and Unrealized Gain (Loss)
Net realized gain (loss) on:
Investment Securities:
Unaffiliated issuers		(79,278,622)
Total net realized gain (loss)				(79,278,622)
Change in net unrealized appreciation (depreciation) on investment securities				72,270,452
Net gain (loss)				(7,008,170)
Net increase (decrease) in net assets resulting from operations			$	152,082,186

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)	$	159,090,356	$	479,279,408
Net realized gain (loss)		(79,278,622)		(462,614,985)
Change in net unrealized appreciation (depreciation)		72,270,452		705,454,556
Net increase (decrease) in net assets resulting from operations		152,082,186		722,118,979
Distributions to shareholders		(114,432,410)		(386,942,076)

Share transactions
Proceeds from sales of shares		942,198,594		3,586,242,122
Reinvestment of distributions		111,133,673		363,499,888
Cost of shares redeemed		(1,704,246,062)		(10,543,429,760)

Net increase (decrease) in net assets resulting from share transactions		(650,913,795)		(6,593,687,750)
Total increase (decrease) in net assets		(613,264,019)		(6,258,510,847)

Net Assets
Beginning of period		9,584,727,765		15,843,238,612
End of period	$	8,971,463,746	$	9,584,727,765

Other Information
Shares
Sold		107,120,083		410,322,514
Issued in reinvestment of distributions		12,589,091		41,664,334
Redeemed		(193,505,070)		(1,196,217,162)
Net increase (decrease)		(73,795,896)		(744,230,314)

Financial Highlights

Fidelity® SAI U.S. Treasury Bond 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	$	8.83	$	8.66	$	8.66	$	9.79	$	10.10	$	10.60
Income from Investment Operations
Net investment income (loss) B,C		.158		.307		.257		.184		.106		.168
Net realized and unrealized gain (loss)		(.004)		.116		(.063)		(1.170)		(.316)		(.191)
Total from investment operations		.154		.423		.194		(.986)		(.210)		(.023)
Distributions from net investment income		(.114)		(.253)		(.194)		(.144)		(.098)		(.175)
Distributions from net realized gain		-		-		-		-		(.002)		(.302)
Total distributions		(.114)		(.253)		(.194)		(.144)		(.100)		(.477)
Net asset value, end of period	$	8.87	$	8.83	$	8.66	$	8.66	$	9.79	$	10.10
Total Return D,E		1.75 %		4.96%		2.25%		(10.10)%		(2.09)%		(.33)%
Ratios to Average Net Assets C,F,G
Expenses before reductions		.04% H		.04%		.05%		.05%		.05%		.05%
Expenses net of fee waivers, if any		.03 % H		.03%		.03%		.03%		.03%		.03%
Expenses net of all reductions, if any		.03% H		.03%		.03%		.03%		.03%		.03%
Net investment income (loss)		3.57% H		3.51%		2.97%		2.05%		1.06%		1.56%
Supplemental Data
Net assets, end of period (000 omitted)	$	8,971,464	$	9,584,728	$	15,843,239	$	13,457,181	$	11,227,354	$	9,575,368
Portfolio turnover rate I		28 % H		32%		37%		60%		45%		167%

AFor the year ended February 29.

BCalculated based on average shares outstanding during the period.

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

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

FFees 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. For additional expense information related to investments in Fidelity Central Funds, please refer to the "Investments in Fidelity Central Funds" note found in the Notes to Financial Statements section of the most recent Annual or Semi-Annual report.

GExpense 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.

HAnnualized.

IAmount 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 SAI U.S. Treasury Bond Index Fund (the Fund) is a fund of Fidelity Salem Street Trust (the Trust) and is authorized to issue an unlimited number of shares. Shares are offered exclusively to certain clients of Fidelity Management & Research Company LLC (FMR) or its affiliates. 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 Massachusetts business trust.

2. Investments in Fidelity Central Funds.

Fidelity Central Fund	Investment Manager	Investment Objective	Investment Practices	Expense RatioA
Fidelity Money Market Central Funds	Fidelity Management & Research Company LLC (FMR)	Each fund seeks to obtain a high level of current income consistent with the preservation of capital and liquidity.	Short-term Investments	Less than .005%