Quarterly Holdings Report

for

Fidelity® Series Treasury Bill Index Fund

January 31, 2024

XSB-NPRT3-0324

1.9891221.105

U.S. Government and Government Agency Obligations - 99.9%
	Principal Amount (a)	Value ($)
U.S. Treasury Obligations - 99.9%
U.S. Treasury Bills, yield at date of purchase:
0%:
7/5/24	80,060,000	78,345,966
8/1/24	82,420,000	80,341,606
5.08% to 5.32% 5/7/24 to 7/25/24	1,284,820,000	1,261,440,252
TOTAL U.S. GOVERNMENT AND GOVERNMENT AGENCY OBLIGATIONS (Cost $1,420,165,659)		1,420,127,824

TOTAL INVESTMENT IN SECURITIES - 99.9% (Cost $1,420,165,659)	1,420,127,824
NET OTHER ASSETS (LIABILITIES) - 0.1%	1,300,795
NET ASSETS - 100.0%	1,421,428,619

Legend

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

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 ($)	% ownership, end of period
Fidelity Cash Central Fund 5.39%	8,931,866	225,358,981	234,290,847	138,605	-	-	-	0.0%
Total	8,931,866	225,358,981	234,290,847	138,605	-	-	-

Amounts in the dividend income column in the above table include any capital gain distributions from underlying funds.

Investment Valuation

Investments are valued as of 4:00 p.m. Eastern time on the last calendar day of the period. Securities transactions are accounted for as of trade date. 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 inputs to valuation techniques used to value investments are categorized 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 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.

Changes in valuation techniques may result in transfers in or out of an assigned level within the disclosure hierarchy.

For additional information on the Fund's significant accounting policies, please refer to the Fund's most recent semiannual or annual shareholder report.

The fund's schedule of investments as of the date on the cover of this report has not been audited. This report is provided for the general information of the fund's shareholders. For more information regarding the fund and its holdings, please see the fund's most recent prospectus and annual report.

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