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 811-7139

Fidelity Hereford Street Trust
(Exact name of registrant as specified in charter)

245 Summer St., Boston, Massachusetts 02210
(Address of principal executive offices) (Zip code)

Scott C. Goebel, 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:	April 30

Date of reporting period:	April 30, 2015

Item 1. Reports to Stockholders

ContentsShareholder Expense ExampleInvestment Changes/Performance (Unaudited)Investments April 30, 2015Financial StatementsNotes to Financial StatementsReport of Independent Registered Public Accounting FirmTrustees and OfficersDistributions (Unaudited)ContentsShareholder Expense ExampleInvestment Changes/Performance (Unaudited)Investments April 30, 2015Financial StatementsNotes to Financial StatementsReport of Independent Registered Public Accounting FirmTrustees and OfficersDistributions (Unaudited)ContentsShareholder Expense ExampleInvestment Changes/Performance (Unaudited)Investments April 30, 2015Financial StatementsNotes to Financial StatementsReport of Independent Registered Public Accounting FirmTrustees and OfficersDistributions (Unaudited)Board Approval of Investment Advisory Contracts and Management FeesContentsShareholder Expense ExampleInvestment Changes/Performance (Unaudited)Investments April 30, 2015Financial StatementsNotes to Financial StatementsReport of Independent Registered Public Accounting FirmTrustees and OfficersDistributions (Unaudited)Board Approval of Investment Advisory Contracts and Management Fees

Fidelity®

Treasury Money Market
Fund

Annual Report

April 30, 2015

(Fidelity Cover Art)

Shareholder Expense Example	(Click Here)	An example of shareholder expenses.
Investment Changes/Performance	(Click Here)	A summary of major shifts in the fund's investments over the past six months and one year.
Investments	(Click Here)	A complete list of the fund's investments.
Financial Statements	(Click Here)	Statements of assets and liabilities, operations, and changes in net assets, as well as financial highlights.
Notes	(Click Here)	Notes to the financial statements.
Report of Independent Registered Public Accounting Firm	(Click Here)
Trustees and Officers	(Click Here)
Distributions	(Click Here)

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-Q. Forms N-Q are available on the SEC's web site at http://www.sec.gov. A fund's Forms N-Q 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.advisor.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.

Annual Report

Shareholder Expense Example

As a shareholder of the Fund, you incur two types of costs: (1) transaction costs, and (2) ongoing costs, including management fees and other Fund expenses. This Example is intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds.

The Example is based on an investment of $1,000 invested at the beginning of the period and held for the entire period (November 1, 2014 to April 30, 2015).

Actual Expenses

The first line of the accompanying table provides information about actual account values and actual expenses. You may use the information in this line, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000.00 (for example, an $8,600 account value divided by $1,000.00 = 8.6), then multiply the result by the number in the first line under the heading entitled "Expenses Paid During Period" to estimate the expenses you paid on your account during this period. A small balance maintenance fee of $12.00 that is charged once a year may apply for certain accounts with a value of less than $2,000. This fee is not included in the table below. If it was, the estimate of expenses you paid during the period would be higher, and your ending account value lower, by this amount.

Hypothetical Example for Comparison Purposes

The second line of the accompanying table provides information about hypothetical account values and hypothetical expenses based on the Fund's actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Fund's actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds. A small balance maintenance fee of $12.00 that is charged once a year may apply for certain accounts with a value of less than $2,000. This fee is not included in the table below. If it was, the estimate of expenses you paid during the period would be higher, and your ending account value lower, by this amount.

Please note that the expenses shown in the table are meant to highlight your ongoing costs only and do not reflect any transaction costs. Therefore, the second line of the table is useful in comparing ongoing costs only, and will not help you determine the relative total costs of owning different funds.

Annual Report

	Annualized Expense Ratio^B	Beginning Account Value November 1, 2014	Ending Account Value April 30, 2015	Expenses Paid During Period* November 1, 2014 to April 30, 2015
Actual	.08%	$ 1,000.00	$ 1,000.05	$ .40
Hypothetical^A		$ 1,000.00	$ 1,024.40	$ .40

^A 5% return per year before expenses

^B Annualized expense ratio reflects expenses net of applicable fee waivers.

* Expenses are equal to the Fund's annualized expense ratio, multiplied by the average account value over the period, multiplied by 181/365 (to reflect the one-half year period).

Annual Report

Investment Changes/Performance (Unaudited)

Effective Maturity Diversification
Days	% of fund's investments 4/30/15	% of fund's investments 10/31/14	% of fund's investments 4/30/14
1 - 7	81.2	74.7	69.9
8 - 30	1.2	2.6	6.9
31 - 60	3.1	0.8	3.8
61 - 90	1.6	6.6	4.1
91 - 180	6.9	7.5	10.4
> 180	6.0	7.8	4.9

Effective maturity is determined in accordance with the requirements of Rule 2a-7 under the Investment Company Act of 1940.

Weighted Average Maturity
	4/30/15	10/31/14	4/30/14
Fidelity® Treasury Money Market Fund	26 Days	37 Days	32 Days
Treasury Retail Money Market Funds Average*	55 Days	53 Days	52 Days

This is a weighted average of all the maturities of the securities held in a fund. Weighted Average Maturity (WAM) can be used as a measure of sensitivity to interest rate changes and market changes. Generally, the longer the maturity, the greater the sensitivity to such changes. WAM is based on the dollar-weighted average length of time until principal payments must be paid. Depending on the types of securities held in a fund, certain maturity shortening devices (e.g., demand features, interest rate resets, and call options) may be taken into account when calculating the WAM.

Weighted Average Life
	4/30/15	10/31/14	4/30/14
Fidelity® Treasury Money Market Fund	31 Days	53 Days	45 Days

Weighted Average Life (WAL) is the weighted average of the life of the securities held in a fund or portfolio and can be used as a measure of sensitivity to changes in liquidity and/or credit risk. Generally, the higher the value, the greater the sensitivity. WAL is based on the dollar-weighted average length of time until principal payments must be paid, taking into account any call options exercised by the issuer and any permissible maturity shortening features other than interest rate resets. The difference between WAM and WAL is that WAM takes into account interest rate resets and WAL does not. WAL for money market funds is not the same as WAL of a mortgage- or asset-backed security.

* Source: iMoneyNet, Inc.

Annual Report

Asset Allocation (% of fund's net assets)
As of April 30, 2015		As of October 31, 2014
	Treasury Debt 19.5%		Treasury Debt 25.1%
	Repurchase Agreements 80.1%		Repurchase Agreements 74.5%
	Net Other Assets (Liabilities) 0.4%		Net Other Assets (Liabilities) 0.4%

for208

Current and Historical Seven-Day Yields

	4/30/15	1/31/15	10/31/14	7/31/14	4/30/14

Fidelity Treasury Money Market Fund	0.01%	0.01%	0.01%	0.01%	0.01%

Yield refers to income paid by the fund over a given period. Yields for money market funds are usually for seven-day periods, as they are here, though they are expressed as annual percentage rates. Past performance is no guarantee of future results. Yield will vary and it's possible to lose money investing in the Fund. A portion of the Fund's expenses was reimbursed and/or waived. Absent such reimbursements and/or waivers the yield for the period ending April 30, 2015, the most recent period shown in the table, would have been -0.33%.

Annual Report

Investments April 30, 2015

Showing Percentage of Net Assets

Treasury Debt - 19.5%
		Yield (a)	Principal Amount	Value
U.S. Treasury Obligations - 19.5%
U.S. Treasury Bills
	7/9/15 to 9/17/15	0.12 to 0.15%	$ 12,000,000	$ 11,994,601
U.S. Treasury Notes
	5/15/15 to 10/31/16	0.07 to 0.33 (b)	122,870,000	123,290,872
TOTAL TREASURY DEBT (Cost $135,285,473)				135,285,473

Treasury Repurchase Agreement - 80.1%
	Maturity Amount
In a joint trading account at 0.11% dated 4/30/15 due 5/1/15 (Collateralized by U.S. Treasury Obligations) #	$ 495,534,572	495,533,000
With:
BNP Paribas Securities Corp. at 0.08%, dated:
4/24/15 due 5/7/15 (Collateralized by U.S. Treasury Obligations valued at $33,740,272, 0.1% - 7.13%,12/31/15 - 8/15/42)	33,002,347	33,000,000
4/27/15 due 5/7/15 (Collateralized by U.S. Treasury Obligations valued at $25,514,451, 0.1% - 8.13%, 7/31/16 - 11/15/44)	25,001,667	25,000,000
Wells Fargo Securities, LLC at 0.12%, dated 3/16/15 due 6/15/15 (Collateralized by U.S. Treasury Obligations valued at $3,060,544, 1%, 5/31/18)	3,000,910	3,000,000
TOTAL TREASURY REPURCHASE AGREEMENT (Cost $556,533,000)		556,533,000
TOTAL INVESTMENT PORTFOLIO - 99.6% (Cost $691,818,473)		691,818,473
NET OTHER ASSETS (LIABILITIES) - 0.4%		2,961,896
NET ASSETS - 100%		$ 694,780,369

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) Coupon rates for floating and adjustable rate securities reflect the rates in effect at period end.

# Additional information on each counterparty to the repurchase agreement is as follows:

Repurchase Agreement / Counterparty	Value
$495,533,000 due 5/01/15 at 0.11%
Citibank NA	$ 37,000,000
Credit Agricole CIB New York Branch	160,533,000
Merrill Lynch, Pierce, Fenner & Smith, Inc.	25,000,000
Mizuho Securities USA, Inc.	250,000,000
Societe Generale	23,000,000
	$ 495,533,000

Other Information

The date shown for securities represents the date when principal payments must be paid, taking into account any call options exercised by the issuer and any permissible maturity shortening features other than interest rate resets.

All investments are categorized as Level 2 under the Fair Value Hierarchy. 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, please refer to the Security Valuation section in the accompanying Notes to Financial Statements.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements

Statement of Assets and Liabilities

	April 30, 2015

Assets
Investment in securities, at value (including repurchase agreements of $556,533,000) - See accompanying schedule: Unaffiliated issuers (cost $691,818,473)		$ 691,818,473
Receivable for fund shares sold		18,353,928
Interest receivable		398,140
Receivable from investment adviser for expense reductions		187
Total assets		710,570,728

Liabilities
Payable to custodian bank	$ 19
Payable for fund shares redeemed	15,736,249
Distributions payable	1,159
Accrued management fee	52,932
Total liabilities		15,790,359

Net Assets		$ 694,780,369
Net Assets consist of:
Paid in capital		$ 694,780,290
Accumulated undistributed net realized gain (loss) on investments		79
Net Assets, for 694,779,724 shares outstanding		$ 694,780,369
Net Asset Value, offering price and redemption price per share ($694,780,369 ÷ 694,779,724 shares)		$ 1.00

See accompanying notes which are an integral part of the financial statements.

Annual Report

Statement of Operations

	Year ended April 30, 2015

Investment Income
Interest		$ 221,153

Expenses
Management fee	$ 1,048,321
Independent trustees' compensation	801
Tax expense	187
Total expenses before reductions	1,049,309
Expense reductions	(852,926)	196,383
Net investment income (loss)		24,770
Realized and Unrealized Gain (Loss) Net realized gain (loss) on:
Investment securities:
Unaffiliated issuers		582
Net increase in net assets resulting from operations		$ 25,352

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements - continued

Statement of Changes in Net Assets

	Year ended April 30, 2015	For the period July 2, 2013 (commencement of operations) to April 30, 2014
Increase (Decrease) in Net Assets
Operations
Net investment income (loss)	$ 24,770	$ 2,615
Net realized gain (loss)	582	56
Net increase in net assets resulting from operations	25,352	2,671
Distributions to shareholders from net investment income	(24,766)	(2,612)
Share transactions at net asset value of $1.00 per share Proceeds from sales of shares	1,988,342,590	157,468,607
Reinvestment of distributions	19,505	2,183
Cost of shares redeemed	(1,364,899,868)	(86,153,293)
Net increase (decrease) in net assets and shares resulting from share transactions	623,462,227	71,317,497
Total increase (decrease) in net assets	623,462,813	71,317,556

Net Assets
Beginning of period	71,317,556	-
End of period	$ 694,780,369	$ 71,317,556

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights

Years ended April 30,	2015	2014 ^D
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00	$ 1.00
Income from Investment Operations
Net investment income (loss) ^F	-	-
Distributions from net investment income ^F	-	-
Net asset value, end of period	$ 1.00	$ 1.00
Total Return^{B, C}	.01%	.01%
Ratios to Average Net Assets ^E
Expenses before reductions	.42%	.42% ^A
Expenses net of fee waivers, if any	.08%	.06% ^A
Expenses net of all reductions	.08%	.06% ^A
Net investment income (loss)	.01%	.01% ^A
Supplemental Data
Net assets, end of period (000 omitted)	$ 694,780	$ 71,318

^A Annualized

^B Total returns for periods of less than one year are not annualized.

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

^D For the period July 2, 2013 (commencement of operations) to April 30, 2014.

^E Expense ratios reflect operating expenses of the Fund. Expenses before reductions do not reflect amounts reimbursed or waived or reductions from expense offset arrangements and do not represent the amount paid by the Fund during periods when reimbursements, waivers or reductions occur. Expenses net of fee waivers reflect expenses after reimbursement and waivers but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the Fund.

^F Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Notes to Financial Statements

For the period ended April 30, 2015

1. Organization.

Fidelity® Treasury Money Market Fund (the Fund) is a fund of Fidelity Hereford 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 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. In January 2015 the Board of Trustees approved to close the Fund to new accounts with certain exceptions effective May 22, 2015.

2. Significant Accounting Policies.

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. Subsequent events, if any, through the date that the financial statements were issued have been evaluated in the preparation of the financial statements. The following summarizes the significant accounting policies of the Fund:

Security Valuation. 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 - 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)

As permitted by compliance with certain conditions under Rule 2a-7 of the 1940 Act, securities are valued at amortized cost, which approximates fair value. The amortized cost of an instrument is determined by valuing it at its original cost and thereafter amortizing any discount or premium from its face value at a constant rate until maturity. Securities held by a money market fund are generally high quality and liquid; however, they are reflected as Level 2 because the inputs used to determine fair value are not quoted prices in an active market.

Annual Report

Notes to Financial Statements - continued

2. Significant Accounting Policies - continued

Investment Transactions and Income - continued

amortization of premium and accretion of discount on debt securities as applicable. The principal amount on inflation-indexed securities is periodically adjusted to the rate of inflation and interest is accrued based on the principal amount. The adjustments to principal due to inflation are reflected as increases or decreases to Interest in the accompanying Statement of Operations.

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. 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. During the period, the Fund incurred an excise tax liability on undistributed net investment income which is included in Tax expense on the Statement of Operations. As of April 30, 2015, the Fund did not have any unrecognized tax benefits in the financial statements; nor is the Fund aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months. 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.

Dividends 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. In addition, the Fund claimed a portion of the payment made to redeeming shareholders as a distribution for income tax purposes. There were no significant book-to-tax differences during the period.

The federal tax cost of investment securities and unrealized appreciation (depreciation) as of period end were as follows:

Gross unrealized appreciation	$ -
Gross unrealized depreciation	-
Net unrealized appreciation (depreciation) on securities	$ -

Tax Cost	$ 691,818,473

Annual Report

2. Significant Accounting Policies - continued

Income Tax Information and Distributions to Shareholders - continued

The tax-based components of distributable earnings as of period end were as follows:

Undistributed ordinary income

$ 79

The tax character of distributions paid was as follows:

	April 30, 2015	April 30, 2014
Ordinary Income	$ 24,766	$ 2,612

Repurchase Agreements. Pursuant to an Exemptive Order issued by the Securities and Exchange Commission (the SEC), the Fund along with other registered investment companies having management contracts with Fidelity Management & Research Company (FMR), or other affiliated entities of FMR, are permitted to transfer uninvested cash balances into joint trading accounts which are then invested in repurchase agreements. The Fund may also invest directly with institutions in repurchase agreements. Repurchase agreements may be collateralized by government or non-government securities. Upon settlement date, collateral is held in segregated accounts with custodian banks and may be obtained in the event of a default of the counterparty. The Fund monitors, on a daily basis, the value of the collateral to ensure it is at least equal to the principal amount of the repurchase agreement (including accrued interest). In the event of a default by the counterparty, realization of the collateral proceeds could be delayed, during which time the value of the collateral may decline.

New Accounting Pronouncement. In June 2014, the Financial Accounting Standards Board issued Accounting Standard Update No. 2014-11, Repurchase-to-Maturity Transactions, Repurchase Financings, and Disclosures (the Update). The Update amends the accounting for certain repurchase agreements and expands disclosure requirements for reverse repurchase agreements, securities lending and other similar transactions. The disclosure requirements are effective for annual and interim reporting periods beginning after December 15, 2014. Management is currently evaluating the impact of the Update on the Fund's financial statements and related disclosures.

New Rule Issuance. In July 2014, the U.S. Securities and Exchange Commission issued Final Rule Release No. 33-9616, Money Market Fund Reform; Amendments to Form PF, which amends the rules governing money market funds. The final amendments impose different implementation dates for the changes that certain money market funds will need to make. Management is currently evaluating the implication of these amendments and their impact of the Final Rule to the Fund's financial statements and related disclosures.

Annual Report

Notes to Financial Statements - continued

3. Fees and Other Transactions with Affiliates.

Management Fee. Fidelity Management & Research Company (the investment adviser) and its affiliates provide the Fund with investment management related services for which the Fund pays a monthly management fee that is based on an annual rate of .42% of the Fund's average net assets. Under the management contract, the investment adviser pays all other 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.

4. Expense Reductions.

The investment adviser or its affiliates voluntarily agreed to waive certain fees in order to maintain a minimum annualized yield of .01%. Such arrangements may be discontinued by the investment adviser at any time. For the period, the amount of the waiver was $852,920.

In addition, through arrangements with the Fund's custodian, credits realized as a result of uninvested cash balances were used to reduce the Fund's management fee. During the period, these credits reduced the Fund's management fee by $1.

In addition, the investment adviser reimbursed a portion of the Fund's operating expenses during the period in the amount of $5.

5. Proposed Reorganization.

The Board of Trustees of the Fund approved an Agreement and Plan of Reorganization (the Agreement) between the Fund and Treasury Fund. Pursuant to the Agreement, Treasury Fund will acquire all the assets and assume all the liabilities of the Fund. The reorganization will be accomplished by an exchange of shares of the Fund for Treasury Fund shares of Treasury Fund at a net asset value of $1.00 on the date the reorganization is effective. The reorganization provides shareholders of Fidelity Treasury Money Market Fund access to a larger portfolio with a similar investment objective.

The reorganization does not require shareholder approval and is expected to become effective on or about June 19, 2015. The reorganization is expected to qualify as a tax-free transaction for federal income tax purposes with no gain or loss recognized by the funds or their shareholders.

Annual Report

6. Other.

The 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, the Fund may also enter into contracts that provide general indemnifications. The Fund's maximum exposure under these arrangements is unknown as this would be dependent on future claims that may be made against the Fund. The risk of material loss from such claims is considered remote.

Annual Report

Report of Independent Registered Public Accounting Firm

To the Trustees of Fidelity Hereford Street Trust and Shareholders of Fidelity Treasury Money Market Fund:

We have audited the accompanying statement of assets and liabilities of Fidelity Treasury Money Market Fund (the Fund), a fund of Fidelity Hereford Street Trust, including the schedule of investments, as of April 30, 2015, and the related statement of operations for the year then ended, and the statements of changes in net assets and the financial highlights for the year ended and for the period from July 2, 2013 (commencement of operations) to April 30, 2014. These financial statements and financial highlights are the responsibility of the Fund's management. Our responsibility is to express an opinion on these financial statements and financial highlights based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements and financial highlights are free of material misstatement. The Fund is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Fund's internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. Our procedures included confirmation of securities owned as of April 30, 2015, by correspondence with the custodians and brokers; where replies were not received from brokers, we performed other auditing procedures. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the financial statements and financial highlights referred to above present fairly, in all material respects, the financial position of Fidelity Treasury Money Market Fund as of April 30, 2015, the results of its operations for the year then ended, and the changes in its net assets and the financial highlights for the year ended and for the period from July 2, 2013 (commencement of operations) to April 30, 2014 , in conformity with accounting principles generally accepted in the United States of America.

DELOITTE & TOUCHE LLP

Boston, Massachusetts

June 16, 2015

Annual Report

Trustees and Officers

The Trustees, Member of the Advisory Board, and officers of the trust and fund, as applicable, are listed below. The Board of Trustees governs the fund and is responsible for protecting the interests of shareholders. The Trustees are experienced executives who meet periodically throughout the year to oversee the fund's activities, review contractual arrangements with companies that provide services to the fund, oversee management of the risks associated with such activities and contractual arrangements, and review the fund's performance. Except for Elizabeth S. Acton and John Engler, each of the Trustees oversees 235 funds. Ms. Acton and Mr. Engler each oversees 217 funds.

The Trustees hold office without limit in time except that (a) any Trustee may resign; (b) any Trustee may be removed by written instrument, signed by at least two-thirds of the number of Trustees prior to such removal; (c) any Trustee who requests to be retired or who has become incapacitated by illness or injury may be retired by written instrument signed by a majority of the other Trustees; and (d) any Trustee may be removed at any special meeting of shareholders by a two-thirds vote of the outstanding voting securities of the trust. Each Trustee who is not an interested person (as defined in the 1940 Act) of the trust and the fund (Independent Trustee), shall retire not later than the last day of the month in which his or her 75th birthday occurs. The Independent Trustees may waive this mandatory retirement age policy with respect to individual Trustees. The officers and Advisory Board Member hold office without limit in time, except that any officer and Advisory Board Member may resign or may be removed by a vote of a majority of the Trustees at any regular meeting or any special meeting of the Trustees. Except as indicated, each individual has held the office shown or other offices in the same company for the past five years.

Experience, Skills, Attributes, and Qualifications of the Fund's Trustees. The Governance and Nominating Committee has adopted a statement of policy that describes the experience, qualifications, attributes, and skills that are necessary and desirable for potential Independent Trustee candidates (Statement of Policy). The Board believes that each Trustee satisfied at the time he or she was initially elected or appointed a Trustee, and continues to satisfy, the standards contemplated by the Statement of Policy. The Governance and Nominating Committee also engages professional search firms to help identify potential Independent Trustee candidates who have the experience, qualifications, attributes, and skills consistent with the Statement of Policy. From time to time, additional criteria based on the composition and skills of the current Independent Trustees, as well as experience or skills that may be appropriate in light of future changes to board composition, business conditions, and regulatory or other developments, have also been considered by the professional search firms and the Governance and Nominating Committee. In addition, the Board takes into account the Trustees' commitment and participation in Board and committee meetings, as well as their leadership of standing and ad hoc committees throughout their tenure.

In determining that a particular Trustee was and continues to be qualified to serve as a Trustee, the Board has considered a variety of criteria, none of which, in isolation, was controlling. The Board believes that, collectively, the Trustees have balanced and diverse experience, qualifications, attributes, and skills, which allow the Board to operate effectively in governing the fund and protecting the interests of shareholders. Information about the specific experience, skills, attributes, and qualifications of each Trustee, which in each case led to the Board's conclusion that the Trustee should serve (or continue to serve) as a trustee of the fund, is provided below.

Annual Report

Board Structure and Oversight Function. Abigail P. Johnson is an interested person (as defined in the 1940 Act) and currently serves as Chairman. The Trustees have determined that an interested Chairman is appropriate and benefits shareholders because an interested Chairman has a personal and professional stake in the quality and continuity of services provided to the fund. Independent Trustees exercise their informed business judgment to appoint an individual of their choosing to serve as Chairman, regardless of whether the Trustee happens to be independent or a member of management. The Independent Trustees have determined that they can act independently and effectively without having an Independent Trustee serve as Chairman and that a key structural component for assuring that they are in a position to do so is for the Independent Trustees to constitute a substantial majority for the Board. The Independent Trustees also regularly meet in executive session. Albert R. Gamper, Jr. serves as Chairman of the Independent Trustees and as such (i) acts as a liaison between the Independent Trustees and management with respect to matters important to the Independent Trustees and (ii) with management prepares agendas for Board meetings.

Fidelity funds are overseen by different Boards of Trustees. The fund's Board oversees Fidelity's investment-grade bond, money market, and asset allocation funds and other Boards oversee Fidelity's equity and high income funds. The asset allocation funds may invest in Fidelity funds that are overseen by such other Boards. The use of separate Boards, each with its own committee structure, allows the Trustees of each group of Fidelity funds to focus on the unique issues of the funds they oversee, including common research, investment, and operational issues. On occasion, the separate Boards establish joint committees to address issues of overlapping consequences for the Fidelity funds overseen by each Board.

The Trustees operate using a system of committees to facilitate the timely and efficient consideration of all matters of importance to the Trustees, the fund, and fund shareholders and to facilitate compliance with legal and regulatory requirements and oversight of the fund's activities and associated risks. The Board, acting through its committees, has charged FMR and its affiliates with (i) identifying events or circumstances the occurrence of which could have demonstrably adverse effects on the fund's business and/or reputation; (ii) implementing processes and controls to lessen the possibility that such events or circumstances occur or to mitigate the effects of such events or circumstances if they do occur; and (iii) creating and maintaining a system designed to evaluate continuously business and market conditions in order to facilitate the identification and implementation processes described in (i) and (ii) above. Because the day-to-day operations and activities of the fund are carried out by or through FMR, its affiliates, and other service providers, the fund's exposure to risks is mitigated but not eliminated by the processes overseen by the Trustees. While each of the Board's committees has responsibility for overseeing different aspects of the fund's activities, oversight is exercised primarily through the Operations and Audit Committees. In addition, an ad hoc Board committee of Independent Trustees has worked with FMR to enhance the Board's oversight of investment and financial risks, legal and regulatory risks, technology risks, and operational risks, including the development of additional risk reporting to the Board. The Operations Committee also worked and continues to work with FMR to enhance the stress tests required under SEC regulations for money market funds. Appropriate personnel, including but not limited to the fund's Chief Compliance Officer (CCO), FMR's internal auditor, the independent accountants, the fund's Treasurer and portfolio management personnel, make periodic reports to the Board's committees, as appropriate, including an annual review of FMR's risk management program for the Fidelity funds. The responsibilities of each standing committee, including their oversight responsibilities, are described further under "Standing Committees of the Fund's Trustees."

Annual Report

Trustees and Officers - continued

The fund's Statement of Additional Information (SAI) includes more information about the Trustees. To request a free copy, call Fidelity at 1-800-544-8544.

Interested Trustee*:

Correspondence intended for the Trustee who is an interested person may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Abigail P. Johnson (1961)
Year of Election or Appointment: 2009 Trustee Chairman of the Board of Trustees
	Ms. Johnson also serves as Trustee of other Fidelity funds. Ms. Johnson serves as President (2013-present) and Chief Executive Officer (2014-present) of FMR LLC (diversified financial services company), President of Fidelity Financial Services (2012-present) and President of Personal, Workplace and Institutional Services (2005-present). Ms. Johnson is Chairman and Director of FMR Co., Inc. (investment adviser firm, 2011-present), Chairman and Director of FMR (investment adviser firm, 2011-present), and the Vice Chairman and Director (2007-present) of FMR LLC. Previously, Ms. Johnson served as President and a Director of FMR (2001-2005), a Trustee of other investment companies advised by FMR, Fidelity Investments Money Management, Inc. (investment adviser firm), and FMR Co., Inc. (2001-2005), Senior Vice President of the Fidelity funds (2001-2005), and managed a number of Fidelity funds. Ms. Abigail P. Johnson and Mr. Arthur E. Johnson are not related.

Annual Report

* Trustee has been determined to be an "Interested Trustee" by virtue of, among other things, her affiliation with the trust or various entities under common control with FMR.

⁺ The information above includes the Trustee's principal occupation during the last five years and other information relating to the experience, attributes, and skills relevant to the Trustee's qualifications to serve as a Trustee, which led to the conclusion that the Trustee should serve as a Trustee for the fund.

Independent Trustees:

Correspondence intended for each Independent Trustee (that is, the Trustees other than the Interested Trustee) may be sent to Fidelity Investments, P.O. Box 55235, Boston, Massachusetts 02205-5235.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Elizabeth S. Acton (1951)
Year of Election or Appointment: 2013 Trustee
	Ms. Acton also serves as Trustee or Member of the Advisory Board of other Fidelity funds. Prior to her retirement in April 2012, Ms. Acton was Executive Vice President, Finance (2011-2012), Executive Vice President, Chief Financial Officer (2002-2011), and Treasurer (2004-2005) of Comerica Incorporated (financial services). Prior to joining Comerica, Ms. Acton held a variety of positions at Ford Motor Company (1983-2002), including Vice President and Treasurer (2000-2002) and Executive Vice President and Chief Financial Officer of Ford Motor Credit Company (1998-2000). Ms. Acton currently serves as a member of the Board of Directors and Audit and Finance Committees of Beazer Homes USA, Inc. (homebuilding, 2012-present).
John Engler (1948)
Year of Election or Appointment: 2014 Trustee
	Mr. Engler also serves as Trustee or Member of the Advisory Board of other Fidelity funds. He serves as president of the Business Roundtable (2011-present), and on the board of directors/trustees for Universal Forest Products (manufacturer and distributor of wood and wood-alternative products, 2003-present), K12 Inc. (technology-based education company, 2012-present), and the Annie E. Casey Foundation (2004-present). Previously, Mr. Engler served as a trustee of The Munder Funds (2003-2014), president and CEO of the National Association of Manufacturers (2004-2011) and as governor of Michigan (1991-2003). He is a past chairman of the National Governors Association.
Albert R. Gamper, Jr. (1942)
Year of Election or Appointment: 2006 Trustee Chairman of the Independent Trustees
	Mr. Gamper also serves as Trustee of other Fidelity funds. Prior to his retirement in December 2004, Mr. Gamper served as Chairman of the Board of CIT Group Inc. (commercial finance). During his tenure with CIT Group Inc. Mr. Gamper served in numerous senior management positions, including Chairman (1987-1989; 1999-2001; 2002-2004), Chief Executive Officer (1987-2004), and President (2002-2003). Mr. Gamper currently serves as a member of the Board of Directors of Public Service Enterprise Group (utilities, 2000-present), and Member of the Board of Trustees of Barnabas Health Care System (1997-present). Previously, Mr. Gamper served as Vice Chairman of the Independent Trustees of certain Fidelity funds (2011-2012) and as Chairman of the Board of Governors, Rutgers University (2004-2007).
Robert F. Gartland (1951)
Year of Election or Appointment: 2010 Trustee
	Mr. Gartland also serves as Trustee of other Fidelity funds. Mr. Gartland is Chairman and an investor in Gartland and Mellina Group Corp. (consulting, 2009-present). Previously, Mr. Gartland served as a partner and investor of Vietnam Partners LLC (investments and consulting, 2008-2011). Prior to his retirement, Mr. Gartland held a variety of positions at Morgan Stanley (financial services, 1979-2007) including Managing Director (1987-2007).
Arthur E. Johnson (1947)
Year of Election or Appointment: 2008 Trustee
	Mr. Johnson also serves as Trustee of other Fidelity funds. Mr. Johnson serves as a member of the Board of Directors of Eaton Corporation plc (diversified power management, 2009-present), AGL Resources, Inc. (holding company, 2002-present) and Booz Allen Hamilton (management consulting, 2011-present). Prior to his retirement, Mr. Johnson served as Senior Vice President of Corporate Strategic Development of Lockheed Martin Corporation (defense contractor, 1999-2009). He previously served on the Board of Directors of IKON Office Solutions, Inc. (1999-2008) and Delta Airlines (2005-2007). Mr. Arthur E. Johnson is not related to Ms. Abigail P. Johnson.
Michael E. Kenneally (1954)
Year of Election or Appointment: 2009 Trustee
	Mr. Kenneally also serves as Trustee of other Fidelity funds. Mr. Kenneally served as a Member of the Advisory Board for certain Fidelity funds before joining the Board of Trustees (2008-2009). Prior to his retirement, Mr. Kenneally served as Chairman and Global Chief Executive Officer of Credit Suisse Asset Management. Before joining Credit Suisse, he was an Executive Vice President and Chief Investment Officer for Bank of America Corporation. Earlier roles at Bank of America included Director of Research, Senior Portfolio Manager and Research Analyst, and Mr. Kenneally was awarded the Chartered Financial Analyst (CFA) designation in 1991.
James H. Keyes (1940)
Year of Election or Appointment: 2007 Trustee
	Mr. Keyes also serves as Trustee of other Fidelity funds. Mr. Keyes serves as a member of the Board and Non-Executive Chairman of Navistar International Corporation (manufacture and sale of trucks, buses, and diesel engines, since 2002). Previously, Mr. Keyes served as a member of the Board of Pitney Bowes, Inc. (integrated mail, messaging, and document management solutions, 1998-2013). Prior to his retirement, Mr. Keyes served as Chairman (1993-2002) and Chief Executive Officer (1988-2002) of Johnson Controls (automotive, building, and energy) and as a member of the Board of LSI Logic Corporation (semiconductor technologies, 1984-2008).
Marie L. Knowles (1946)
Year of Election or Appointment: 2001 Trustee Vice Chairman of the Independent Trustees
	Ms. Knowles also serves as Trustee of other Fidelity funds. Prior to Ms. Knowles' retirement in June 2000, she served as Executive Vice President and Chief Financial Officer of Atlantic Richfield Company (ARCO) (diversified energy, 1996-2000). From 1993 to 1996, she was a Senior Vice President of ARCO and President of ARCO Transportation Company. She served as a Director of ARCO from 1996 to 1998. Ms. Knowles currently serves as a Director and Chairman of the Audit Committee of McKesson Corporation (healthcare service, since 2002). Ms. Knowles is a member of the Board of the Catalina Island Conservancy and of the Santa Catalina Island Company (2009-present). She also serves as a member of the Advisory Board for the School of Engineering of the University of Southern California. Previously, Ms. Knowles served as a Director of Phelps Dodge Corporation (copper mining and manufacturing, 1994-2007), URS Corporation (engineering and construction, 2000-2003) and America West (airline, 1999-2002).

⁺ The information above includes each Trustee's principal occupation during the last five years and other information relating to the experience, attributes, and skills relevant to each Trustee's qualifications to serve as a Trustee, which led to the conclusion that each Trustee should serve as a Trustee for the fund.

Annual Report

Advisory Board Member and Officers:

Correspondence intended for each officer and Geoffrey A. von Kuhn may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210. Officers appear below in alphabetical order.

Name, Year of Birth; Principal Occupation
Geoffrey A. von Kuhn (1951)
Year of Election or Appointment: 2015 Member of the Advisory Board
	Mr. von Kuhn also serves as a Trustee or Member of the Advisory Board of other Fidelity funds. Mr. von Kuhn is Chief Administrative Officer for FMR LLC (diversified financial services company, 2013-present), a Director of Pembroke Real Estate, Inc. (2009-present), and a Director of Discovery Natural Resources LLC (2012-present). Previously, Mr. von Kuhn was a managing director of Crosby Group (private wealth management company, 2007-2013), a member of the management committee and senior executive in the Wealth Management Group of AmSouth Bank (2001-2006), and head of the U.S. private bank at Citigroup (2000-2001).
Elizabeth Paige Baumann (1968)
Year of Election or Appointment: 2012 Anti-Money Laundering (AML) Officer
	Ms. Baumann also serves as AML Officer of other funds. She is Chief AML Officer of FMR LLC (diversified financial services company, 2012-present) and is an employee of Fidelity Investments. Previously, Ms. Baumann served as Vice President and Deputy Anti-Money Laundering Officer (2007-2012).
Marc Bryant (1966)
Year of Election or Appointment: 2013 Assistant Secretary
	Mr. Bryant also serves as an officer of other funds. He is Senior Vice President and Deputy General Counsel of FMR LLC (diversified financial services company). Previously, Mr. Bryant served as Secretary and Chief Legal Officer of Fidelity Rutland Square Trust II (2010-2014). Prior to joining Fidelity Investments, Mr. Bryant served as a Senior Vice President and the Head of Global Retail Legal for AllianceBernstein L.P. (2006-2010), and as the General Counsel for ProFund Advisors LLC (2001-2006).
Jonathan Davis (1968)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Davis also serves as Assistant Treasurer of other funds. Mr. Davis is an employee of Fidelity Investments. Previously, Mr. Davis served as Vice President and Associate General Counsel of FMR LLC (diversified financial services company, 2003-2010).
Adrien E. Deberghes (1967)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Deberghes also serves as an officer of other funds. He is an employee of Fidelity Investments (2008-present). Prior to joining Fidelity Investments, Mr. Deberghes was Senior Vice President of Mutual Fund Administration at State Street Corporation (2007-2008), Senior Director of Mutual Fund Administration at Investors Bank & Trust (2005-2007), and Director of Finance for Dunkin' Brands (2000-2005).
Stephanie J. Dorsey (1969)
Year of Election or Appointment: 2013 President and Treasurer
	Ms. Dorsey also serves as an officer of other funds. She is an employee of Fidelity Investments (2008-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Dorsey served as Treasurer (2004-2008) of the JPMorgan Mutual Funds and Vice President (2004-2008) of JPMorgan Chase Bank.
Howard J. Galligan III (1966)
Year of Election or Appointment: 2014 Chief Financial Officer
	Mr. Galligan also serves as Chief Financial Officer of other funds. Mr. Galligan serves as President of Fidelity Pricing and Cash Management Services (FPCMS) (2014-present) and as a Director of Strategic Advisers, Inc. (investment adviser firm, 2008-present). Previously, Mr. Galligan served as Chief Administrative Officer of Asset Management (2011-2014) and Chief Operating Officer and Senior Vice President of Investment Support for Strategic Advisers, Inc. (2003-2011).
Scott C. Goebel (1968)
Year of Election or Appointment: 2008 Secretary and Chief Legal Officer (CLO)
	Mr. Goebel serves as Secretary and CLO of other funds. Mr. Goebel also serves as Secretary of Fidelity SelectCo, LLC (investment adviser firm, 2013-present), Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2010-present) and Fidelity Research and Analysis Company (FRAC) (investment adviser firm, 2010-present); General Counsel, Secretary, and Senior Vice President of FMR (investment adviser firm, 2008-present) and FMR Co., Inc. (investment adviser firm, 2008-present); Chief Legal Officer of Fidelity Management & Research (Hong Kong) Limited (investment adviser firm, 2008-present); and Assistant Secretary of Fidelity Management & Research (Japan) Limited (investment adviser firm, 2008-present) and FMR Investment Management (U.K.) Limited (investment adviser firm, 2008-present). Previously, Mr. Goebel served as Secretary and CLO of other Fidelity funds (2008-2013), Assistant Secretary of FIMM (2008-2010), FRAC (2008-2010), and certain funds (2007-2008); and as Vice President and Secretary of Fidelity Distributors Corporation (FDC) (2005-2007). Mr. Goebel has been employed by FMR LLC (diversified financial services company) or an affiliate since 2001.
Chris Maher (1972)
Year of Election or Appointment: 2013 Assistant Treasurer
	Mr. Maher serves as Assistant Treasurer of other funds. Mr. Maher is Vice President of Valuation Oversight and is an employee of Fidelity Investments. Previously, Mr. Maher served as Vice President of Asset Management Compliance (2013), Vice President of the Program Management Group of FMR (investment adviser firm, 2010-2013), and Vice President of Valuation Oversight (2008-2010).
Nancy D. Prior (1967)
Year of Election or Appointment: 2014 Vice President
	Ms. Prior also serves as Vice President of other funds. Ms. Prior serves as a Director of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2014-present), President, Fixed Income (2014-present), Vice Chairman of Pyramis Global Advisors, LLC (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2002-present). Previously, Ms. Prior served as Vice President of Fidelity's Money Market Funds (2012-2014), President, Money Market and Short Duration Bond of FMR (investment adviser firm, 2013-2014), President, Money Market Group of FMR (2011-2014), Managing Director of Research (2009-2011), Senior Vice President and Deputy General Counsel (2007-2009), and Assistant Secretary of other Fidelity funds (2008-2009).
Kenneth B. Robins (1969)
Year of Election or Appointment: 2009 Assistant Treasurer
	Mr. Robins also serves as an officer of other funds. Mr. Robins serves as Executive Vice President of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2013-present) and is an employee of Fidelity Investments (2004-present). Previously, Mr. Robins served in other fund officer roles.
Stephen Sadoski (1971)
Year of Election or Appointment: 2013 Deputy Treasurer
	Mr. Sadoski also serves as Deputy Treasurer of other funds. He is an employee of Fidelity Investments (2012-present) and has served in another fund officer role. Prior to joining Fidelity Investments, Mr. Sadoski served as an assistant chief accountant in the Division of Investment Management of the Securities and Exchange Commission (SEC) (2009-2012) and as a senior manager at Deloitte & Touche LLP (1997-2009).
Stacie M. Smith (1974)
Year of Election or Appointment: 2013 Assistant Treasurer
	Ms. Smith also serves as an officer of other funds. She is an employee of Fidelity Investments (2009-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Smith served as Senior Audit Manager of Ernst & Young LLP (1996-2009).
Renee Stagnone (1975)
Year of Election or Appointment: 2013 Deputy Treasurer
	Ms. Stagnone also serves as Deputy Treasurer of other funds. Ms. Stagnone is an employee of Fidelity Investments.
Michael H. Whitaker (1967)
Year of Election or Appointment: 2008 Chief Compliance Officer
	Mr. Whitaker also serves as Chief Compliance Officer of other funds. Mr. Whitaker also serves as Compliance Officer of FMR Co., Inc. (investment adviser firm, 2014-present), FMR (investment adviser firm, 2014-present), Fidelity Investments Money Management, Inc. (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2007-present). Prior to joining Fidelity Investments, Mr. Whitaker worked at MFS Investment Management where he served as Senior Vice President and Chief Compliance Officer (2004-2006), and Assistant General Counsel.
Joseph F. Zambello (1957)
Year of Election or Appointment: 2011 Deputy Treasurer
	Mr. Zambello also serves as Deputy Treasurer of other funds. Mr. Zambello is an employee of Fidelity Investments. Previously, Mr. Zambello served as Vice President of the Program Management Group of FMR (investment adviser firm, 2009-2011) and Vice President of the Transfer Agent Oversight Group (2005-2009).

Annual Report

Distributions (Unaudited)

A total of 28.50% of the dividends distributed during the fiscal year was derived from interest on U.S. Government securities which is generally exempt from state income tax.

The fund designates $12,546 of distributions paid during the period January 1, 2015 to April 30, 2015 as qualifying to be taxed as interest-related dividends for nonresident alien shareholders.

The fund will notify shareholders in January 2016 of amounts for use in preparing 2015 income tax returns.

Annual Report

Investment Adviser

Fidelity Management & Research
Company
Boston, MA

Investment Sub-Advisers

Fidelity Investments
Money Management, Inc.

FMR Investment Management
(U.K.) Limited

Fidelity Management & Research
(Hong Kong) Limited

Fidelity Management & Research
(Japan) Limited

General Distributor

Fidelity Distributors Corporation

Smithfield, RI

Transfer and Service Agents

Fidelity Investments Institutional
Operations Company, Inc.

Boston, MA

Fidelity Service Company, Inc.

Boston, MA

Custodian

The Bank of New York Mellon

New York, NY

The Fidelity Telephone Connection

Mutual Fund 24-Hour Service

Exchanges/Redemptions
and Account Assistance 1-800-544-6666

Product Information 1-800-544-6666

Retirement Accounts 1-800-544-4774 (8 a.m. - 9 p.m.)

TDD Service 1-800-544-0118
for the deaf and hearing impaired
(9 a.m. - 9 p.m. Eastern time)

Fidelity Automated Service
Telephone (FAST®) for210
1-800-544-5555

Automated line for quickest service

(Fidelity Investment logo)(registered trademark)
Corporate Headquarters
245 Summer St., Boston, MA 02210
www.fidelity.com

FTM-ANN-0615
1.964318.101

Fidelity®

Treasury Only Money Market
Fund

Annual Report

April 30, 2015

(Fidelity Cover Art)

Shareholder Expense Example	(Click Here)	An example of shareholder expenses.
Investment Changes/Performance	(Click Here)	A summary of major shifts in the fund's investments over the past six months and one year.
Investments	(Click Here)	A complete list of the fund's investments.
Financial Statements	(Click Here)	Statements of assets and liabilities, operations, and changes in net assets, as well as financial highlights.
Notes	(Click Here)	Notes to the financial statements.
Report of Independent Registered Public Accounting Firm	(Click Here)
Trustees and Officers	(Click Here)
Distributions	(Click Here)

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.

Annual Report

Shareholder Expense Example

The Example is based on an investment of $1,000 invested at the beginning of the period and held for the entire period (November 1, 2014 to April 30, 2015).

Actual Expenses

Hypothetical Example for Comparison Purposes

Annual Report

	Annualized Expense Ratio^B	Beginning Account Value November 1, 2014	Ending Account Value April 30, 2015	Expenses Paid During Period* November 1, 2014 to April 30, 2015
Actual	.05%	$ 1,000.00	$ 1,000.05	$ .25
Hypothetical^A		$ 1,000.00	$ 1,024.55	$ .25

^A 5% return per year before expenses

^B Annualized expense ratio reflects expenses net of applicable fee waivers.

* Expenses are equal to the Fund's annualized expense ratio, multiplied by the average account value over the period, multiplied by 181/365 (to reflect the one-half year period).

Annual Report

Investment Changes/Performance (Unaudited)

Effective Maturity Diversification
Days	% of fund's investments 4/30/15	% of fund's investments 10/31/14	% of fund's investments 4/30/14
1 - 7	12.6	9.7	2.5
8 - 30	17.2	22.4	29.0
31 - 60	17.3	22.0	21.9
61 - 90	25.7	15.3	22.3
91 - 180	27.2	30.6	24.3

Effective maturity is determined in accordance with the requirements of Rule 2a-7 under the Investment Company Act of 1940.

Weighted Average Maturity
	4/30/15	10/31/14	4/30/14
Fidelity® Treasury Only Money Market Fund	54 Days	58 Days	56 Days
Treasury Retail Money Market Funds Average*	55 Days	53 Days	52 Days

Weighted Average Life
	4/30/15	10/31/14	4/30/14
Fidelity® Treasury Only Money Market Fund	95 Days	93 Days	72 Days

* Source: iMoneyNet, Inc.

Annual Report

Asset Allocation (% of fund's net assets)
As of April 30, 2015		As of October 31, 2014
	Treasury Debt 99.7%		Treasury Debt 99.7%
	Net Other Assets (Liabilities) 0.3%		Net Other Assets (Liabilities) 0.3%

for230

Current and Historical Seven-Day Yields

	4/30/15	1/31/15	10/31/14	7/31/14	4/30/14
Fidelity® Treasury Only Money Market Fund	0.01%	0.01%	0.01%	0.01%	0.01%

Yield refers to the income paid by the fund over a given period. Yields for money market funds are usually for seven-day periods, as they are here, though they are expressed as annual percentage rates. Past performance is no guarantee of future results. Yield will vary and it's possible to lose money investing in the Fund. A portion of the Fund's expenses was reimbursed and/or waived. Absent such reimbursements and/or waivers the yield for the period ending April 30, 2015, the most recent period shown in the table, would have been -0.36%.

Annual Report

Investments April 30, 2015

Showing Percentage of Net Assets

Treasury Debt - 99.7%
		Yield (a)	Principal Amount (000s)	Value (000s)
U.S. Treasury Obligations - 99.7%
U.S. Treasury Bills
	5/7/15 to 10/1/15	0.01 to 0.15%	$ 1,316,914	$ 1,316,783
U.S. Treasury Notes
	5/15/15 to 10/31/16	0.03 to 0.13 (b)	3,256,159	3,264,781

TOTAL INVESTMENT PORTFOLIO - 99.7%

(Cost $4,581,564)

4,581,564

NET OTHER ASSETS (LIABILITIES) - 0.3%

14,948

NET ASSETS - 100%

$ 4,596,512

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) Coupon rates for floating and adjustable rate securities reflect the rates in effect at period end.

Other Information

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements

Statement of Assets and Liabilities

Amounts in thousands (except per-share amount)	April 30, 2015

Assets
Investment in securities, at value - See accompanying schedule: Unaffiliated issuers (cost $4,581,564)		$ 4,581,564
Cash		94
Receivable for fund shares sold		3,700
Interest receivable		18,141
Receivable from investment adviser for expense reductions		10
Total assets		4,603,509

Liabilities
Payable for fund shares redeemed	$ 6,771
Distributions payable	3
Accrued management fee	221
Other affiliated payables	2
Total liabilities		6,997

Net Assets		$ 4,596,512
Net Assets consist of:
Paid in capital		$ 4,596,434
Accumulated undistributed net realized gain (loss) on investments		78
Net Assets, for 4,595,720 shares outstanding		$ 4,596,512
Net Asset Value, offering price and redemption price per share ($4,596,512 ÷ 4,595,720 shares)		$ 1.00

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements - continued

Statement of Operations

Amounts in thousands	Year ended April 30, 2015

Investment Income
Interest		$ 2,672

Expenses
Management fee	$ 20,375
Independent trustees' compensation	20
Tax expense	10
Total expenses before reductions	20,405
Expense reductions	(18,220)	2,185
Net investment income (loss)		487
Realized and Unrealized Gain (Loss) Net realized gain (loss) on:
Investment securities:
Unaffiliated issuers		20
Net increase in net assets resulting from operations		$ 507

See accompanying notes which are an integral part of the financial statements.

Annual Report

Statement of Changes in Net Assets

Amounts in thousands	Year ended April 30, 2015	Year ended April 30, 2014
Increase (Decrease) in Net Assets
Operations
Net investment income (loss)	$ 487	$ 572
Net realized gain (loss)	20	23
Net increase in net assets resulting from operations	507	595
Distributions to shareholders from net investment income	(488)	(573)
Share transactions at net asset value of $1.00 per share Proceeds from sales of shares	1,405,172	2,011,451
Reinvestment of distributions	452	531
Cost of shares redeemed	(1,864,322)	(2,624,764)
Net increase (decrease) in net assets and shares resulting from share transactions	(458,698)	(612,782)
Total increase (decrease) in net assets	(458,679)	(612,760)

Net Assets
Beginning of period	5,055,191	5,667,951
End of period	$ 4,596,512	$ 5,055,191

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights

Years ended April 30,	2015	2014	2013	2012	2011
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Income from Investment Operations
Net investment income (loss) ^C	-	-	-	-	-
Net realized and unrealized gain (loss) ^C	-	-	-	-	-
Total from investment operations ^C	-	-	-	-	-
Distributions from net investment income ^C	-	-	-	-	-
Net asset value, end of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Total Return^A	.01%	.01%	.01%	.01%	.01%
Ratios to Average Net Assets ^B
Expenses before reductions	.42%	.42%	.42%	.42%	.42%
Expenses net of fee waivers, if any	.05%	.06%	.10%	.05%	.17%
Expenses net of all reductions	.04%	.06%	.10%	.05%	.17%
Net investment income (loss)	.01%	.01%	.01%	.01%	.01%
Supplemental Data
Net assets, end of period (in millions)	$ 4,597	$ 5,055	$ 5,668	$ 6,044	$ 4,722

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

^B Expense ratios reflect operating expenses of the Fund. Expenses before reductions do not reflect amounts reimbursed or waived or reductions from expense offset arrangements and do not represent the amount paid by the Fund during periods when reimbursements, waivers or reductions occur. Expenses net of fee waivers reflect expenses after reimbursement and waivers but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the Fund.

^C Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Notes to Financial Statements

For the period ended April 30, 2015

(Amounts in thousands except percentages)

1. Organization.

Fidelity Treasury Only Money Market Fund (the Fund) is a fund of Fidelity Hereford 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 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.

2. Significant Accounting Policies.

Security Valuation. 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 - 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)

Annual Report

2. Significant Accounting Policies - continued

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. During the period, the Fund incurred an excise tax liability on undistributed net investment income and undistributed short-term capital gain, which is included in Tax expense on the Statement of Operations. As of April 30, 2015, the Fund did not have any unrecognized tax benefits in the financial statements; nor is the Fund aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months. 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.

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 deferred trustees compensation and losses deferred due to wash sales and excise tax regulations.

The federal tax cost of investment securities and unrealized appreciation (depreciation) as of period end were as follows:

Gross unrealized appreciation	$ -
Gross unrealized depreciation	-
Net unrealized appreciation (depreciation) on securities	$ -

Tax Cost	$ 4,581,564

Annual Report

Notes to Financial Statements - continued

(Amounts in thousands except percentages)

2. Significant Accounting Policies - continued

Income Tax Information and Distributions to Shareholders - continued

The tax-based components of distributable earnings as of period end were as follows:

Undistributed ordinary income

$ 86

The Fidelity Treasury Only Money Market Fund elected to defer to its next fiscal year approximately $6 of capital losses recognized during the period November 1, 2014 to April 30, 2015.

The tax character of distributions paid was as follows:

	April 30, 2015	April 30, 2014
Ordinary Income	$ 488	$ 573

Reverse Repurchase Agreements. To enhance its yield, the Fund may enter into reverse repurchase transactions under master repurchase agreements whereby the Fund sells securities to a counterparty in return for cash and agrees to repurchase those securities at a future date and agreed upon price. During the period that reverse repurchase transactions are outstanding, the Fund identifies the securities as pledged in its records with an initial value at least equal to its principal obligation under the agreement. The cash proceeds received by the Fund may be invested in other securities. To the extent cash proceeds received from the counterparty exceed the value of the securities sold, the counterparty may request additional collateral from the Fund. If the counterparty defaults on its obligation, because of insolvency or other reasons, the Fund could experience delays and costs in recovering the securities sold. Information regarding securities sold under a reverse repurchase agreement, if any, is included at the end of the Fund's Schedule of Investments and the cash proceeds are recorded as a liability in the accompanying Statement of Assets and Liabilities. The Fund continues to receive interest and dividend payments on the securities sold during the term of the reverse repurchase agreement. At period end, there were no reverse repurchase agreements outstanding.

Annual Report

2. Significant Accounting Policies - continued

3. Fees and Other Transactions with Affiliates.

4. Expense Reductions.

Through arrangements with the Fund's custodian, credits realized as a result of uninvested cash balances were used to reduce the Fund's management fee. During the period, these credits reduced the Fund's management fee by $6.

In addition, the investment adviser reimbursed a portion of the Fund's operating expenses during the period in the amount of $11.

5. Other.

Annual Report

Report of Independent Registered Public Accounting Firm

To the Trustees of Fidelity Hereford Street Trust and the Shareholders of Fidelity Treasury Only Money Market Fund:

In our opinion, the accompanying statement of assets and liabilities, including the schedule of investments, and the related statements of operations and of changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Fidelity Treasury Only Money Market Fund (a fund of Fidelity Hereford Street Trust) at April 30, 2015, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended and the financial highlights for each of the five years in the period then ended, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements") are the responsibility of the Fidelity Treasury Only Money Market Fund's management. Our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at April 30, 2015 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion.

PricewaterhouseCoopers LLP

Boston, Massachusetts

June 16, 2015

Annual Report

Trustees and Officers

Annual Report

Trustees and Officers - continued

The fund's Statement of Additional Information (SAI) includes more information about the Trustees. To request a free copy, call Fidelity at 1-800-544-8544.

Interested Trustee*:

Correspondence intended for the Trustee who is an interested person may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Abigail P. Johnson (1961)
Year of Election or Appointment: 2009 Trustee Chairman of the Board of Trustees
	Ms. Johnson also serves as Trustee of other Fidelity funds. Ms. Johnson serves as President (2013-present) and Chief Executive Officer (2014-present) of FMR LLC (diversified financial services company), President of Fidelity Financial Services (2012-present) and President of Personal, Workplace and Institutional Services (2005-present). Ms. Johnson is Chairman and Director of FMR Co., Inc. (investment adviser firm, 2011-present), Chairman and Director of FMR (investment adviser firm, 2011-present), and the Vice Chairman and Director (2007-present) of FMR LLC. Previously, Ms. Johnson served as President and a Director of FMR (2001-2005), a Trustee of other investment companies advised by FMR, Fidelity Investments Money Management, Inc. (investment adviser firm), and FMR Co., Inc. (2001-2005), Senior Vice President of the Fidelity funds (2001-2005), and managed a number of Fidelity funds. Ms. Abigail P. Johnson and Mr. Arthur E. Johnson are not related.

Annual Report

* Trustee has been determined to be an "Interested Trustee" by virtue of, among other things, her affiliation with the trust or various entities under common control with FMR.

Independent Trustees:

Correspondence intended for each Independent Trustee (that is, the Trustees other than the Interested Trustee) may be sent to Fidelity Investments, P.O. Box 55235, Boston, Massachusetts 02205-5235.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Elizabeth S. Acton (1951)
Year of Election or Appointment: 2013 Trustee
	Ms. Acton also serves as Trustee or Member of the Advisory Board of other Fidelity funds. Prior to her retirement in April 2012, Ms. Acton was Executive Vice President, Finance (2011-2012), Executive Vice President, Chief Financial Officer (2002-2011), and Treasurer (2004-2005) of Comerica Incorporated (financial services). Prior to joining Comerica, Ms. Acton held a variety of positions at Ford Motor Company (1983-2002), including Vice President and Treasurer (2000-2002) and Executive Vice President and Chief Financial Officer of Ford Motor Credit Company (1998-2000). Ms. Acton currently serves as a member of the Board of Directors and Audit and Finance Committees of Beazer Homes USA, Inc. (homebuilding, 2012-present).
John Engler (1948)
Year of Election or Appointment: 2014 Trustee
	Mr. Engler also serves as Trustee or Member of the Advisory Board of other Fidelity funds. He serves as president of the Business Roundtable (2011-present), and on the board of directors/trustees for Universal Forest Products (manufacturer and distributor of wood and wood-alternative products, 2003-present), K12 Inc. (technology-based education company, 2012-present), and the Annie E. Casey Foundation (2004-present). Previously, Mr. Engler served as a trustee of The Munder Funds (2003-2014), president and CEO of the National Association of Manufacturers (2004-2011) and as governor of Michigan (1991-2003). He is a past chairman of the National Governors Association.
Albert R. Gamper, Jr. (1942)
Year of Election or Appointment: 2006 Trustee Chairman of the Independent Trustees
	Mr. Gamper also serves as Trustee of other Fidelity funds. Prior to his retirement in December 2004, Mr. Gamper served as Chairman of the Board of CIT Group Inc. (commercial finance). During his tenure with CIT Group Inc. Mr. Gamper served in numerous senior management positions, including Chairman (1987-1989; 1999-2001; 2002-2004), Chief Executive Officer (1987-2004), and President (2002-2003). Mr. Gamper currently serves as a member of the Board of Directors of Public Service Enterprise Group (utilities, 2000-present), and Member of the Board of Trustees of Barnabas Health Care System (1997-present). Previously, Mr. Gamper served as Vice Chairman of the Independent Trustees of certain Fidelity funds (2011-2012) and as Chairman of the Board of Governors, Rutgers University (2004-2007).
Robert F. Gartland (1951)
Year of Election or Appointment: 2010 Trustee
	Mr. Gartland also serves as Trustee of other Fidelity funds. Mr. Gartland is Chairman and an investor in Gartland and Mellina Group Corp. (consulting, 2009-present). Previously, Mr. Gartland served as a partner and investor of Vietnam Partners LLC (investments and consulting, 2008-2011). Prior to his retirement, Mr. Gartland held a variety of positions at Morgan Stanley (financial services, 1979-2007) including Managing Director (1987-2007).
Arthur E. Johnson (1947)
Year of Election or Appointment: 2008 Trustee
	Mr. Johnson also serves as Trustee of other Fidelity funds. Mr. Johnson serves as a member of the Board of Directors of Eaton Corporation plc (diversified power management, 2009-present), AGL Resources, Inc. (holding company, 2002-present) and Booz Allen Hamilton (management consulting, 2011-present). Prior to his retirement, Mr. Johnson served as Senior Vice President of Corporate Strategic Development of Lockheed Martin Corporation (defense contractor, 1999-2009). He previously served on the Board of Directors of IKON Office Solutions, Inc. (1999-2008) and Delta Airlines (2005-2007). Mr. Arthur E. Johnson is not related to Ms. Abigail P. Johnson.
Michael E. Kenneally (1954)
Year of Election or Appointment: 2009 Trustee
	Mr. Kenneally also serves as Trustee of other Fidelity funds. Mr. Kenneally served as a Member of the Advisory Board for certain Fidelity funds before joining the Board of Trustees (2008-2009). Prior to his retirement, Mr. Kenneally served as Chairman and Global Chief Executive Officer of Credit Suisse Asset Management. Before joining Credit Suisse, he was an Executive Vice President and Chief Investment Officer for Bank of America Corporation. Earlier roles at Bank of America included Director of Research, Senior Portfolio Manager and Research Analyst, and Mr. Kenneally was awarded the Chartered Financial Analyst (CFA) designation in 1991.
James H. Keyes (1940)
Year of Election or Appointment: 2007 Trustee
	Mr. Keyes also serves as Trustee of other Fidelity funds. Mr. Keyes serves as a member of the Board and Non-Executive Chairman of Navistar International Corporation (manufacture and sale of trucks, buses, and diesel engines, since 2002). Previously, Mr. Keyes served as a member of the Board of Pitney Bowes, Inc. (integrated mail, messaging, and document management solutions, 1998-2013). Prior to his retirement, Mr. Keyes served as Chairman (1993-2002) and Chief Executive Officer (1988-2002) of Johnson Controls (automotive, building, and energy) and as a member of the Board of LSI Logic Corporation (semiconductor technologies, 1984-2008).
Marie L. Knowles (1946)
Year of Election or Appointment: 2001 Trustee Vice Chairman of the Independent Trustees
	Ms. Knowles also serves as Trustee of other Fidelity funds. Prior to Ms. Knowles' retirement in June 2000, she served as Executive Vice President and Chief Financial Officer of Atlantic Richfield Company (ARCO) (diversified energy, 1996-2000). From 1993 to 1996, she was a Senior Vice President of ARCO and President of ARCO Transportation Company. She served as a Director of ARCO from 1996 to 1998. Ms. Knowles currently serves as a Director and Chairman of the Audit Committee of McKesson Corporation (healthcare service, since 2002). Ms. Knowles is a member of the Board of the Catalina Island Conservancy and of the Santa Catalina Island Company (2009-present). She also serves as a member of the Advisory Board for the School of Engineering of the University of Southern California. Previously, Ms. Knowles served as a Director of Phelps Dodge Corporation (copper mining and manufacturing, 1994-2007), URS Corporation (engineering and construction, 2000-2003) and America West (airline, 1999-2002).

Annual Report

Advisory Board Member and Officers:

Correspondence intended for each officer and Geoffrey A. von Kuhn may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210. Officers appear below in alphabetical order.

Name, Year of Birth; Principal Occupation
Geoffrey A. von Kuhn (1951)
Year of Election or Appointment: 2015 Member of the Advisory Board
	Mr. von Kuhn also serves as a Trustee or Member of the Advisory Board of other Fidelity funds. Mr. von Kuhn is Chief Administrative Officer for FMR LLC (diversified financial services company, 2013-present), a Director of Pembroke Real Estate, Inc. (2009-present), and a Director of Discovery Natural Resources LLC (2012-present). Previously, Mr. von Kuhn was a managing director of Crosby Group (private wealth management company, 2007-2013), a member of the management committee and senior executive in the Wealth Management Group of AmSouth Bank (2001-2006), and head of the U.S. private bank at Citigroup (2000-2001).
Elizabeth Paige Baumann (1968)
Year of Election or Appointment: 2012 Anti-Money Laundering (AML) Officer
	Ms. Baumann also serves as AML Officer of other funds. She is Chief AML Officer of FMR LLC (diversified financial services company, 2012-present) and is an employee of Fidelity Investments. Previously, Ms. Baumann served as Vice President and Deputy Anti-Money Laundering Officer (2007-2012).
Marc Bryant (1966)
Year of Election or Appointment: 2013 Assistant Secretary
	Mr. Bryant also serves as an officer of other funds. He is Senior Vice President and Deputy General Counsel of FMR LLC (diversified financial services company). Previously, Mr. Bryant served as Secretary and Chief Legal Officer of Fidelity Rutland Square Trust II (2010-2014). Prior to joining Fidelity Investments, Mr. Bryant served as a Senior Vice President and the Head of Global Retail Legal for AllianceBernstein L.P. (2006-2010), and as the General Counsel for ProFund Advisors LLC (2001-2006).
Jonathan Davis (1968)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Davis also serves as Assistant Treasurer of other funds. Mr. Davis is an employee of Fidelity Investments. Previously, Mr. Davis served as Vice President and Associate General Counsel of FMR LLC (diversified financial services company, 2003-2010).
Adrien E. Deberghes (1967)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Deberghes also serves as an officer of other funds. He is an employee of Fidelity Investments (2008-present). Prior to joining Fidelity Investments, Mr. Deberghes was Senior Vice President of Mutual Fund Administration at State Street Corporation (2007-2008), Senior Director of Mutual Fund Administration at Investors Bank & Trust (2005-2007), and Director of Finance for Dunkin' Brands (2000-2005).
Stephanie J. Dorsey (1969)
Year of Election or Appointment: 2013 President and Treasurer
	Ms. Dorsey also serves as an officer of other funds. She is an employee of Fidelity Investments (2008-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Dorsey served as Treasurer (2004-2008) of the JPMorgan Mutual Funds and Vice President (2004-2008) of JPMorgan Chase Bank.
Howard J. Galligan III (1966)
Year of Election or Appointment: 2014 Chief Financial Officer
	Mr. Galligan also serves as Chief Financial Officer of other funds. Mr. Galligan serves as President of Fidelity Pricing and Cash Management Services (FPCMS) (2014-present) and as a Director of Strategic Advisers, Inc. (investment adviser firm, 2008-present). Previously, Mr. Galligan served as Chief Administrative Officer of Asset Management (2011-2014) and Chief Operating Officer and Senior Vice President of Investment Support for Strategic Advisers, Inc. (2003-2011).
Scott C. Goebel (1968)
Year of Election or Appointment: 2008 Secretary and Chief Legal Officer (CLO)
	Mr. Goebel serves as Secretary and CLO of other funds. Mr. Goebel also serves as Secretary of Fidelity SelectCo, LLC (investment adviser firm, 2013-present), Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2010-present) and Fidelity Research and Analysis Company (FRAC) (investment adviser firm, 2010-present); General Counsel, Secretary, and Senior Vice President of FMR (investment adviser firm, 2008-present) and FMR Co., Inc. (investment adviser firm, 2008-present); Chief Legal Officer of Fidelity Management & Research (Hong Kong) Limited (investment adviser firm, 2008-present); and Assistant Secretary of Fidelity Management & Research (Japan) Limited (investment adviser firm, 2008-present) and FMR Investment Management (U.K.) Limited (investment adviser firm, 2008-present). Previously, Mr. Goebel served as Secretary and CLO of other Fidelity funds (2008-2013), Assistant Secretary of FIMM (2008-2010), FRAC (2008-2010), and certain funds (2007-2008); and as Vice President and Secretary of Fidelity Distributors Corporation (FDC) (2005-2007). Mr. Goebel has been employed by FMR LLC (diversified financial services company) or an affiliate since 2001.
Chris Maher (1972)
Year of Election or Appointment: 2013 Assistant Treasurer
	Mr. Maher serves as Assistant Treasurer of other funds. Mr. Maher is Vice President of Valuation Oversight and is an employee of Fidelity Investments. Previously, Mr. Maher served as Vice President of Asset Management Compliance (2013), Vice President of the Program Management Group of FMR (investment adviser firm, 2010-2013), and Vice President of Valuation Oversight (2008-2010).
Nancy D. Prior (1967)
Year of Election or Appointment: 2014 Vice President
	Ms. Prior also serves as Vice President of other funds. Ms. Prior serves as a Director of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2014-present), President, Fixed Income (2014-present), Vice Chairman of Pyramis Global Advisors, LLC (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2002-present). Previously, Ms. Prior served as Vice President of Fidelity's Money Market Funds (2012-2014), President, Money Market and Short Duration Bond of FMR (investment adviser firm, 2013-2014), President, Money Market Group of FMR (2011-2014), Managing Director of Research (2009-2011), Senior Vice President and Deputy General Counsel (2007-2009), and Assistant Secretary of other Fidelity funds (2008-2009).
Kenneth B. Robins (1969)
Year of Election or Appointment: 2009 Assistant Treasurer
	Mr. Robins also serves as an officer of other funds. Mr. Robins serves as Executive Vice President of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2013-present) and is an employee of Fidelity Investments (2004-present). Previously, Mr. Robins served in other fund officer roles.
Stephen Sadoski (1971)
Year of Election or Appointment: 2013 Deputy Treasurer
	Mr. Sadoski also serves as Deputy Treasurer of other funds. He is an employee of Fidelity Investments (2012-present) and has served in another fund officer role. Prior to joining Fidelity Investments, Mr. Sadoski served as an assistant chief accountant in the Division of Investment Management of the Securities and Exchange Commission (SEC) (2009-2012) and as a senior manager at Deloitte & Touche LLP (1997-2009).
Stacie M. Smith (1974)
Year of Election or Appointment: 2013 Assistant Treasurer
	Ms. Smith also serves as an officer of other funds. She is an employee of Fidelity Investments (2009-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Smith served as Senior Audit Manager of Ernst & Young LLP (1996-2009).
Renee Stagnone (1975)
Year of Election or Appointment: 2013 Deputy Treasurer
	Ms. Stagnone also serves as Deputy Treasurer of other funds. Ms. Stagnone is an employee of Fidelity Investments.
Michael H. Whitaker (1967)
Year of Election or Appointment: 2008 Chief Compliance Officer
	Mr. Whitaker also serves as Chief Compliance Officer of other funds. Mr. Whitaker also serves as Compliance Officer of FMR Co., Inc. (investment adviser firm, 2014-present), FMR (investment adviser firm, 2014-present), Fidelity Investments Money Management, Inc. (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2007-present). Prior to joining Fidelity Investments, Mr. Whitaker worked at MFS Investment Management where he served as Senior Vice President and Chief Compliance Officer (2004-2006), and Assistant General Counsel.
Joseph F. Zambello (1957)
Year of Election or Appointment: 2011 Deputy Treasurer
	Mr. Zambello also serves as Deputy Treasurer of other funds. Mr. Zambello is an employee of Fidelity Investments. Previously, Mr. Zambello served as Vice President of the Program Management Group of FMR (investment adviser firm, 2009-2011) and Vice President of the Transfer Agent Oversight Group (2005-2009).

Annual Report

Distributions (Unaudited)

A total of 100% of the dividends distributed during the fiscal year was derived from interest on U.S. Government securities which is generally exempt from state income tax.

The fund designates $3,026 of distributions paid during the period January 1, 2015 to April 30, 2015 as qualifying to be taxed as interest-related dividends for nonresident alien shareholders.

The fund will notify shareholders in January 2016 of amounts for use in preparing 2015 income tax returns.

Annual Report

Investment Adviser

Fidelity Management & Research
Company
Boston, MA

Investment Sub-Advisers

Fidelity Investments
Money Management, Inc.

FMR Investment Management
(U.K.) Limited

Fidelity Management & Research
(Hong Kong) Limited

Fidelity Management & Research
(Japan) Limited

General Distributor

Fidelity Distributors Corporation

Smithfield, RI

Transfer and Service Agents

Fidelity Investments Institutional
Operations Company, Inc.

Boston, MA

Fidelity Service Company, Inc.

Boston, MA

Custodian

JPMorgan Chase Bank

New York, NY

The Fidelity Telephone Connection

Mutual Fund 24-Hour Service

Exchanges/Redemptions
and Account Assistance 1-800-544-6666

Product Information 1-800-544-6666

Retirement Accounts 1-800-544-4774 (8 a.m. - 9 p.m.)

TDD Service 1-800-544-0118
for the deaf and hearing impaired
(9 a.m. - 9 p.m. Eastern time)

Fidelity Automated Service
Telephone (FAST®) for232
1-800-544-5555

Automated line for quickest service

(Fidelity Investment logo)(registered trademark)
Corporate Headquarters
245 Summer St., Boston, MA 02210
www.fidelity.com

TMM-ANN-0615
1.703531.117

Fidelity®

Money Market

Fund

Annual Report

April 30, 2015

(Fidelity Cover Art)

Shareholder Expense Example	(Click Here)	An example of shareholder expenses.
Investment Changes/ Performance	(Click Here)	A summary of major shifts in the fund's investments over the past six months.
Investments	(Click Here)	A complete list of the fund's investments.
Financial Statements	(Click Here)	Statements of assets and liabilities, operations, and changes in net assets, as well as financial highlights.
Notes	(Click Here)	Notes to the financial statements.
Report of Independent Registered Public Accounting Firm	(Click Here)
Trustees and Officers	(Click Here)
Distributions	(Click Here)
Board Approval of Investment Advisory Contracts and Management Fees	(Click Here)

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.

Annual Report

NOT FDIC INSURED • MAY LOSE VALUE • NO BANK GUARANTEE

Neither the fund nor Fidelity Distributors Corporation is a bank.

Annual Report

Shareholder Expense Example

The actual expense Example is based on an investment of $1,000 invested at the beginning
of the period and held for the entire period (November 1, 2014 to April 30, 2015) for Fidelity® Money Market Fund and for the period (April 6, 2015 to April 30, 2015) for Premium Class. The hypothetical expense Example is based on an investment of $1,000 invested for the one-half year period (November 1, 2014 to April 30, 2015).

Actual Expenses

The first line of the accompanying table for each class of the Fund provides information about actual account values and actual expenses. You may use the information in this line, together with the amount you invested, to estimate the expenses that you paid over the period. Simply divide your account value by $1,000.00 (for example, an $8,600 account value divided by $1,000.00 = 8.6), then multiply the result by the number in the first line for a class of the Fund under the heading entitled "Expenses Paid During Period" to estimate the expenses you paid on your account during this period. A small balance maintenance fee of $12.00 that is charged once a year may apply for certain accounts with a value of less than $2,000. This fee is not included in the table below. If it was, the estimate of expenses you paid during the period would be higher, and your ending account value lower, by this amount.

Hypothetical Example for Comparison Purposes

The second line of the accompanying table for each class of the Fund provides information about hypothetical account values and hypothetical expenses based on a Class' actual expense ratio and an assumed rate of return of 5% per year before expenses, which is not the Class' actual return. The hypothetical account values and expenses may not be used to estimate the actual ending account balance or expenses you paid for the period. You may use this information to compare the ongoing costs of investing in the Fund and other funds. To do so, compare this 5% hypothetical example with the 5% hypothetical examples that appear in the shareholder reports of the other funds. A small balance maintenance fee of $12.00 that is charged once a year may apply for certain accounts with a value of less than $2,000. This fee is not included in the table below. If it was, the estimate of expenses you paid during the period would be higher, and your ending account value lower, by this amount.

Annual Report

	Annualized Expense Ratio^B	Beginning Account Value	Ending Account Value April 30, 2015	Expenses Paid During Period
Fidelity Money Market Fund	.27%
Actual		$ 1,000.00	$ 1,000.05	$ 1.34^C
Hypothetical^A		$ 1,000.00	$ 1,023.46	$ 1.35^D
Premium Class	.28%
Actual		$ 1,000.00	$ 1,000.01	$ .19^C
Hypothetical^A		$ 1,000.00	$ 1,023.41	$ 1.40^D

^A 5% return per year before expenses

^B Annualized expense ratio reflects expenses net of applicable fee waivers.

^CActual expenses are equal to each Class' annualized expense ratio; multiplied by the average account value over the period, multiplied by 181/365 (to reflect the one-half year period) for Fidelity Money Market Fund and multiplied by 25/365 (to reflect the period April 6, 2015 to April 30, 2015) for Premium Class.

^D Hypothetical expenses are equal to each Class' annualized expense ratio, multiplied by the average account value over the period, multiplied by 181/365 (to reflect the one-half year period).

Annual Report

Investment Changes/Performance (Unaudited)

Effective Maturity Diversification
Days	% of fund's investments 4/30/15	% of fund's investments 10/31/14	% of fund's investments 4/30/14
1 - 7	38.1	36.1	28.0
8 - 30	17.1	25.0	26.6
31 - 60	16.9	11.1	13.3
61 - 90	14.9	6.6	12.6
91 - 180	11.7	16.0	19.5
> 180	1.3	5.2	0.0

Effective maturity is determined in accordance with the requirements of Rule 2a-7 under the Investment Company Act of 1940.

Weighted Average Maturity
	4/30/15	10/31/14	4/30/14
Fidelity Money Market Fund	39 Days	50 Days	46 Days
All Taxable Money Market Funds Average*	41 Days	47 Days	45 Days

Weighted Average Life
	4/30/15	10/31/14	4/30/14
Fidelity Money Market Fund	71 Days	84 Days	79 Days

* Source: iMoneyNet, Inc.

Annual Report

Asset Allocation (% of fund's net assets)
As of April 30, 2015		As of October 31, 2014
	Certificates of Deposit 59.8%		Certificates of Deposit 59.3%
	Commercial Paper 16.6%		Commercial Paper 10.8%
	Variable Rate Demand Notes (VRDNs) 0.5%		Variable Rate Demand Notes (VRDNs) 0.5%
	Other Notes 1.8%		Other Notes 1.7%
	Treasury Debt 0.0%		Treasury Debt^† 0.0%
	Government Agency Debt 1.5%		Government Agency Debt 2.8%
	Other Instruments 3.5%		Other Instruments 0.4%
	Repurchase Agreements 16.2%		Repurchase Agreements 23.9%
	Net Other Assets (Liabilities) 0.1%		Net Other Assets (Liabilities) 0.6%

^† Amount represents less than 0.1%

for281

Current and Historical Seven-Day Yields

	4/30/15	1/31/15	10/31/14	7/31/14	4/30/14

Fidelity Money Market Fund	0.01%	0.01%	0.01%	0.01%	0.01%

Premium Class	0.01%	N/A	N/A	N/A	N/A

Annual Report

Investments April 30, 2015

Showing Percentage of Net Assets

Certificate of Deposit - 59.8%
		Yield (a)	Principal Amount (000s)	Value (000s)
Domestic Certificates Of Deposit - 1.9%
BMO Harris Bank NA
	8/20/15	0.33%	$ 6,000	$ 6,000
Wells Fargo Bank NA
	8/3/15 to 12/23/15	0.26 to 0.30 (c)	38,000	38,000
				44,000
London Branch, Eurodollar, Foreign Banks - 3.2%
ABN AMRO Bank NV
	5/20/15 to 8/3/15	0.28 to 0.31	29,000	28,988
Credit Agricole SA
	8/5/15	0.30	11,000	11,000
National Australia Bank Ltd.
	7/7/15 to 9/23/15	0.30	34,000	34,000
				73,988
New York Branch, Yankee Dollar, Foreign Banks - 54.7%
Bank of Montreal
	7/14/15 to 1/5/16	0.26 to 0.29 (c)	24,000	24,000
Bank of Montreal Chicago CD Program
	7/9/15 to 1/11/16	0.27 to 0.40 (c)	37,000	37,000
Bank of Nova Scotia
	7/13/15 to 1/15/16	0.27 to 0.36 (c)	52,000	52,000
Bank of Tokyo-Mitsubishi UFJ Ltd.
	6/3/15 to 8/4/15	0.27	100,000	100,000
Barclays Bank PLC
	6/29/15 to 6/30/15	0.30	59,000	59,000
BNP Paribas New York Branch
	7/1/15	0.27	22,000	22,000
Canadian Imperial Bank of Commerce
	10/1/15 to 1/12/16	0.31 to 0.36 (c)	53,000	53,000
Credit Agricole CIB
	5/4/15	0.29	9,000	9,000
Credit Industriel et Commercial
	5/6/15	0.14	54,000	54,000
Credit Suisse
	6/11/15 to 9/14/15	0.33 to 0.38 (c)	87,000	87,000
Landesbank Baden-Wuerttemberg New York Branch
	5/1/15 to 5/22/15	0.16 to 0.27	111,000	111,000
Certificate of Deposit - continued
		Yield (a)	Principal Amount (000s)	Value (000s)
New York Branch, Yankee Dollar, Foreign Banks - continued
Lloyds TSB Bank PLC New York Branch
	5/6/15	0.14%	$ 18,000	$ 18,000
Mizuho Corporate Bank Ltd.
	5/4/15 to 7/28/15	0.28 to 0.29	85,000	85,000
Natexis Banques Populaires New York Branch
	6/1/15 to 7/31/15	0.28 to 0.31 (c)	115,000	115,000
National Bank of Canada
	6/8/15	0.37 (c)	5,000	5,000
Royal Bank of Canada
	11/10/15 to 3/23/16	0.27 to 0.30 (c)	52,000	52,000
Skandinaviska Enskilda Banken
	8/5/15	0.27	23,000	23,000
Sumitomo Mitsui Banking Corp.
	5/5/15 to 10/15/15	0.28 to 0.38 (c)	116,000	116,000
Sumitomo Mitsui Trust Banking Ltd.
	6/5/15 to 9/11/15	0.29	84,000	84,000
Toronto-Dominion Bank
	6/12/15 to 10/6/15	0.27 to 0.31 (c)	69,000	69,000
Toronto-Dominion Bank New York Branch
	2/12/16	0.29 (c)	13,000	13,000
UBS AG
	6/9/15 to 9/25/15	0.34 to 0.37 (c)	80,000	80,000
				1,268,000
TOTAL CERTIFICATE OF DEPOSIT (Cost $1,385,988)				1,385,988
Financial Company Commercial Paper - 9.6%

Bank of Nova Scotia
	8/17/15	0.31	10,000	9,991
BNP Paribas New York Branch
	8/4/15	0.28	24,000	23,982
DNB Bank ASA
	8/24/15	0.30	9,000	8,991
Fortis Funding LLC
	7/6/15	0.27	6,000	5,997
Financial Company Commercial Paper - continued
		Yield (a)	Principal Amount (000s)	Value (000s)
JPMorgan Securities LLC
	5/26/15 to 11/2/15	0.30 to 0.31% (c)	$ 43,000	$ 42,995
Landesbank Baden-Wurttemberg
	5/21/15	0.25	4,000	3,999
Lloyds Bank PLC
	5/1/15 to 5/6/15	0.13	97,000	96,999
Nationwide Building Society
	7/27/15	0.44	5,000	4,995
Sumitomo Trust & Banking Co. Ltd.
	8/31/15	0.29	24,000	23,976
TOTAL FINANCIAL COMPANY COMMERCIAL PAPER (Cost $221,925)				221,925
Asset Backed Commercial Paper - 2.7%

Atlantic Asset Securitization Corp. (Credit Agricole CIB Guaranteed)

	5/1/15	0.13	30,138	30,138
	5/1/15	0.13	6,000	6,000
	6/9/15	0.27	4,000	3,999
Sheffield Receivables Corp. (Barclays Bank PLC Guaranteed)

	7/13/15	0.30	12,000	11,993
	7/28/15	0.30	10,000	9,993
TOTAL ASSET BACKED COMMERCIAL PAPER (Cost $62,123)				62,123
Other Commercial Paper - 4.3%

Caisse centrale Desjardins
	5/1/15 to 5/5/15	0.14	84,000	84,000
Eversource Energy
	5/14/15	0.52	2,500	2,500
Florida Power & Light Co.
	5/1/15	0.24	13,000	13,000
Other Commercial Paper - continued
		Yield (a)	Principal Amount (000s)	Value (000s)
Xerox Corp.
	5/11/15	0.58	$ 1,000	$ 1,000
TOTAL OTHER COMMERCIAL PAPER (Cost $100,500)				100,500
Other Note - 1.8%

Medium-Term Notes - 1.8%
Dominion Resources, Inc.
	6/15/15	0.38% (b)(c)	7,000	7,000
International Bank Reconstruction & Development
	10/28/15	0.30	9,000	9,000
Svenska Handelsbanken AB
	10/15/15 to 10/27/15	0.33 to 0.35 (b)(c)	26,000	26,000
TOTAL OTHER NOTE (Cost $42,000)				42,000
Variable Rate Demand Note - 0.5%

Delaware - 0.5%
LP Pinewood SPV LLC Taxable, LOC Wells Fargo Bank NA, VRDN
(Cost $11,700)	5/7/15	0.18 (c)	11,700	11,700
Government Agency Debt - 1.5%

Federal Agencies - 1.5%
Federal Home Loan Bank
(Cost $35,000)	10/2/15 to 1/15/16	0.25 to 0.35	35,000	35,000
Other Instrument - 3.5%

Time Deposits - 3.5%
Barclays Bank PLC
	5/1/15	0.14	27,000	27,000
BNP Paribas
	5/1/15	0.08	9,000	9,000
Credit Agricole CIB
	5/1/15	0.10	35,000	35,000
Other Instrument - continued
		Yield (a)	Principal Amount (000s)	Value (000s)
Time Deposits - continued
Fortis Bank (TD)
	5/1/15	0.08%	$ 9,000	$ 9,000
TOTAL OTHER INSTRUMENT (Cost $80,000)				80,000

Government Agency Repurchase Agreement - 5.3%
	Maturity Amount (000s)
In a joint trading account at 0.14% dated 4/30/15 due 5/1/15 (Collateralized by U.S. Government Obligations) #	$ 115,686		115,686
With Mizuho Securities U.S.A., Inc. at 0.18%, dated 1/15/15 due 5/7/15 (Collateralized by U.S. Treasury Obligations valued at $7,707,221, 0% - 1.25%, 10/29/15 - 10/31/15)	7,557		7,552
TOTAL GOVERNMENT AGENCY REPURCHASE AGREEMENT (Cost $123,238)		123,238
Other Repurchase Agreement - 10.9%

Other Repurchase Agreement - 10.9%
With:
BNP Paribas Securities Corp. at 0.28%, dated 4/10/15 due 5/7/15 (Collateralized by Corporate Obligations valued at $1,050,172, 1.75% - 8.5%, 7/15/16 - 3/15/22)	1,000		1,000
Citigroup Global Markets, Inc. at 1%, dated 11/18/14 due 6/16/15 (Collateralized by Corporate Obligations valued at $6,509,521, 0.5%, 2/25/36)	6,035		6,000
Credit Suisse Securities (U.S.A.) LLC at:
0.38%, dated 4/30/15 due 5/1/15 (Collateralized by Corporate Obligations valued at $1,082,921, 5.88%, 5/1/27)	1,000		1,000
0.46%, dated 4/29/15 due 5/6/15 (Collateralized by U.S. Government Obligations valued at $6,180,199, 0.78%, 5/16/55)	6,001		6,000
0.81%, dated 4/6/15 due 8/6/15 (Collateralized by U.S. Government Obligations valued at $3,091,679, 0.33%, 10/16/48)	3,008		3,000
0.83%, dated:
4/2/15 due 8/20/15 (Collateralized by U.S. Government Obligations valued at $5,153,577, 0.84%, 2/16/50)	5,016		5,000
4/6/15 due 9/8/15 (Collateralized by U.S. Government Obligations valued at $4,122,512, 0.79% - 0.84%, 2/16/50 - 8/16/52)	4,014		4,000
Other Repurchase Agreement - continued
	Maturity Amount (000s)		Value (000s)
Other Repurchase Agreement - continued
With: - continued
Credit Suisse Securities (U.S.A.) LLC at:
4/8/15 due 8/26/15 (Collateralized by U.S. Government Obligations valued at $2,061,138, 0.45%, 9/16/53)	$ 2,006		$ 2,000
4/10/15 due 9/14/15 (Collateralized by U.S. Government Obligations valued at $1,030,569, 0.45%, 9/16/53)	1,004		1,000
4/21/15 due 9/18/15 (Collateralized by U.S. Government Obligations valued at $3,090,759, 0.33% - 0.79%, 10/16/48 - 8/16/52)	3,010		3,000
0.85%, dated 4/27/15 due 9/3/15 (Collateralized by U.S. Government Obligations valued at $2,060,323, 0.33% - 0.45%, 10/16/48 - 9/16/53)	2,006		2,000
ING Financial Markets LLC at 0.28%, dated 4/30/15 due 5/1/15 (Collateralized by Corporate Obligations valued at $35,644,230, 3.88% - 9%, 11/1/15 - 2/15/25)	33,000		33,000
J.P. Morgan Clearing Corp. at:
0.34%, dated 4/27/15 due 5/7/15 (Collateralized by Equity Securitites valued at $5,434,989)	5,001		5,000
0.73%, dated 2/19/15 due 7/29/15 (Collateralized by Corporate Obligations valued at $8,708,273, 2.75% - 2.80%, 1/15/16 - 1/15/20)	8,029		8,000
J.P. Morgan Securities, LLC at:
0.25%, dated 4/29/15 due 5/6/15 (Collateralized by U.S. Government Obligations valued at $9,270,396, 6.02%, 12/25/42 - 1/25/43)	9,000		9,000
0.73%, dated:
2/4/15 due 7/29/15 (Collateralized by Mortgage Loan Obligations valued at $6,491,194, 0.47% - 1.71%, 5/25/44 - 1/15/49)	6,022		6,000
2/9/15 due 7/29/15 (Collateralized by Equity Securities valued at $6,510,287)	6,022		6,000
2/12/15 due 7/29/15 (Collateralized by Mortgage Loan Obligations valued at $14,063,661, 0.41% - 5.99%, 7/25/36 - 8/10/45)	13,047		13,000
3/11/15 due 7/29/15 (Collateralized by Mortgage Loan Obligations valued at $2,162,954, 6.15%, 9/11/42)	2,007		2,000
Merrill Lynch, Pierce, Fenner & Smith at:
0.23%, dated 4/30/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $12,360,080, 3.5% - 4%, 4/16/28 - 3/25/38)	12,001		12,000
Other Repurchase Agreement - continued
	Maturity Amount (000s)		Value (000s)
Other Repurchase Agreement - continued
With: - continued
Merrill Lynch, Pierce, Fenner & Smith at:
0.5%, dated 4/30/15 due 5/1/15 (Collateralized by U.S. Government Obligations valued at $11,330,158, 0%, 4/25/45)	$ 11,000		$ 11,000
0.81%, dated 3/6/15 due 6/4/15 (Collateralized by Equity Securities valued at $11,894,984)	11,022		11,000
0.87%, dated 4/8/15 due 5/6/15 (Collateralized by Mortgage Loan Obligations valued at $15,128,404, 0.57% - 6%, 10/25/35 - 5/25/36)	14,009		14,000
0.95%, dated 2/25/15 due 6/25/15 (Collateralized by Corporate Obligations valued at $6,491,115, 0.5% - 4.23%, 4/25/38 - 2/12/41)	6,019		6,000
0.96%, dated 4/2/15 due 8/4/15 (Collateralized by Corporate Obligations valued at $12,970,022, 0.4% - 6%, 4/25/35 - 2/25/37)	12,040		12,000
Mitsubishi UFJ Securities (U.S.A.), Inc. at:
0.26%, dated:
4/2/15 due 5/4/15 (Collateralized by Equity Securities valued at $2,160,455)	2,000		2,000
4/10/15 due 5/7/15 (Collateralized by Equity Securities valued at $5,400,857)	5,001		5,000
4/14/15 due 5/7/15 (Collateralized by Equity Securities valued at $2,160,279)	2,000		2,000
4/22/15 due 5/7/15 (Collateralized by Equity Securities valued at $1,080,071)	1,000		1,000
4/27/15 due 5/7/15 (Collateralized by Equity Securities valued at $1,057,662)	1,000		1,000
0.31%, dated:
4/9/15 due 5/7/15 (Collateralized by Municipal Bond Obligations valued at $2,100,326, 0% - 7.43%, 6/2/15 - 5/15/45)	2,000		2,000
4/13/15 due 5/7/15 (Collateralized by Municipal Bond Obligations valued at $2,100,399, 0% - 7.43%, 1/15/17 - 5/15/45)	2,001		2,000
0.8%, dated 4/24/15 due 6/23/15 (Collateralized by Corporate Obligations valued at $1,080,168, 6.5% - 8.63%, 4/15/16 - 4/15/19)	1,001		1,000
Mizuho Securities U.S.A., Inc. at:
0.18%, dated 4/30/15 due 5/1/15 (Collateralized by U.S. Government Obligations valued at $9,270,047, 10.95%, 6/15/27)	9,000		9,000
0.32%, dated:
4/21/15 due 5/5/15 (Collateralized by Equity Securities valued at $2,160,224)	2,000		2,000
Other Repurchase Agreement - continued
	Maturity Amount (000s)		Value (000s)
Other Repurchase Agreement - continued
With: - continued
Mizuho Securities U.S.A., Inc. at:
4/24/15 due 5/7/15 (Collateralized by Equity Securities valued at $1,080,095)	$ 1,000		$ 1,000
4/29/15 due 5/7/15 (Collateralized by Equity Securities valued at $2,160,056)	2,000		2,000
4/30/15 due 5/7/15 (Collateralized by Equity Securities valued at $3,240,050)	3,000		3,000
0.52%, dated 4/22/15 due 5/6/15 (Collateralized by Corporate Obligations valued at $1,050,137, 1%, 8/15/17)	1,000		1,000
0.91%, dated:
2/2/15 due 5/1/15 (Collateralized by Corporate Obligations valued at $6,494,415, 0.33% - 1.35%, 6/25/35 - 12/25/45)	6,013		6,000
4/15/15 due 7/14/15 (Collateralized by Corporate Obligations valued at $2,160,874, 0.59% - 0.77%, 11/25/35 - 2/25/36)	2,005		2,000
4/20/15 due 7/20/15 (Collateralized by Corporate Obligations valued at $1,080,300, 0.69%, 5/25/35)	1,002		1,000
1.03%, dated 1/5/15 due 5/5/15 (Collateralized by Corporate Obligations valued at $2,167,169, 0.77%, 11/25/35)	2,007		2,000
RBC Capital Markets Co. at:
0.24%, dated 4/29/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $3,096,668, 0% - 11.54%, 2/1/28 - 2/25/45)	3,000		3,000
0.31%, dated 3/23/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $3,090,932, 0% - 6.51%, 2/1/28 - 2/25/45)	3,002		3,000
0.38%, dated:
4/8/15 due 5/7/15 (Collateralized by Equity Securities valued at $2,160,593)	2,002		2,000
4/30/15 due 5/7/15 (Collateralized by Municipal Bond Obligations valued at $2,100,375, 0% - 7.02%, 7/1/22 - 8/1/54)	2,002		2,000
0.4%, dated:
4/9/15 due 5/7/15 (Collateralized by Corporate Obligations valued at $1,080,264, 3.88% - 13%, 3/15/18 - 3/15/32)	1,000		1,000
4/21/15 due 5/5/15 (Collateralized by Mortgage Loan Obligations valued at $1,079,984, 0.31% - 6%,11/15/26 - 10/15/48)	1,000		1,000
Other Repurchase Agreement - continued
	Maturity Amount (000s)		Value (000s)
Other Repurchase Agreement - continued
With: - continued
RBC Capital Markets Co. at:
0.42%, dated 4/9/15 due 5/7/15 (Collateralized by Mortgage Loan Obligations valued at $2,142,796, 0.31% - 5.96%, 11/15/26 - 11/12/49)	$ 2,001		$ 2,000
SG Americas Securities, LLC at:
0.3%, dated 4/30/15 due 5/7/15 (Collateralized by Equity Securities valued at $2,160,020)	2,000		2,000
0.48%, dated 4/29/15 due 5/6/15 (Collateralized by Corporate Obligations valued at $9,666,464, 0.4% - 12%, 9/15/15 - 8/1/69)	9,001		9,000
TOTAL OTHER REPURCHASE AGREEMENT (Cost $252,000)		252,000
TOTAL INVESTMENT PORTFOLIO - 99.9% (Cost $2,314,474)			2,314,474
NET OTHER ASSETS (LIABILITIES) - 0.1%			1,926
NET ASSETS - 100%		$ 2,316,400

Security Type Abbreviations
VRDN	-	VARIABLE RATE DEMAND NOTE (A debt instrument that is payable upon demand, either daily, weekly or monthly)

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) Security exempt from registration under Rule 144A of the Securities Act of 1933. These securities may be resold in transactions exempt from registration, normally to qualified institutional buyers. At the end of the period, the value of these securities amounted to $33,000,000 or 1.4% of net assets.

# Additional information on each counterparty to the repurchase agreement is as follows:

Repurchase Agreement / Counterparty	Value (000s)
$115,686,000 due 5/01/15 at 0.14%
BNY Mellon Capital Markets LLC	$ 23,352
Bank of America NA	29,593
Merrill Lynch, Pierce, Fenner & Smith, Inc.	1,571
Mizuho Securities USA, Inc.	26,536
Societe Generale	3,609
Wachovia Bank NA	20,693
Wells Fargo Securities LLC	10,332
	$ 115,686

Other Information

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements

Statement of Assets and Liabilities

Amounts in thousands (except per-share amounts)	April 30, 2015

Assets
Investment in securities, at value (including repurchase agreements of $375,238) - See accompanying schedule: Unaffiliated issuers (cost $2,314,474)		$ 2,314,474
Receivable for fund shares sold		7,879
Interest receivable		755
Receivable from investment adviser for expense reductions		4
Other receivables		147
Total assets		2,323,259

Liabilities
Payable for investments purchased	$ 3,997
Payable for fund shares redeemed	2,145
Distributions payable	1
Accrued management fee	475
Other affiliated payables	63
Other payables and accrued expenses	178
Total liabilities		6,859

Net Assets		$ 2,316,400
Net Assets consist of:
Paid in capital		$ 2,316,458
Distributions in excess of net investment income		(87)
Accumulated undistributed net realized gain (loss) on investments		29
Net Assets		$ 2,316,400

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements - continued

Statement of Assets and Liabilities - continued

Amounts in thousands (except per-share amounts)	April 30, 2015

Fidelity Money Market Fund: Net Asset Value, offering price and redemption price per share ($2,315,629 ÷ 2,314,610 shares)		$ 1.00

Premium Class: Net Asset Value, offering price and redemption price per share ($771 ÷ 771 shares)		$ 1.00

See accompanying notes which are an integral part of the financial statements.

Annual Report

Statement of Operations

Amounts in thousands	Year ended April 30, 2015

Investment Income
Interest		$ 6,577

Expenses
Management fee	$ 9,375
Transfer agent fees	903
Accounting fees and expenses	56
Custodian fees and expenses	10
Independent trustees' compensation	11
Registration fees	8
Audit	11
Miscellaneous	4
Total expenses before reductions	10,378
Expense reductions	(4,049)	6,329
Net investment income (loss)		248
Realized and Unrealized Gain (Loss) Net realized gain (loss) on:
Investment securities:
Unaffiliated issuers		75
Net increase in net assets resulting from operations		$ 323

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements - continued

Statement of Changes in Net Assets

Amounts in thousands	Year ended April 30, 2015	Year ended April 30, 2014
Increase (Decrease) in Net Assets
Operations
Net investment income (loss)	$ 248	$ 305
Net realized gain (loss)	75	75
Net increase in net assets resulting from operations	323	380
Distributions to shareholders from net investment income	(249)	(311)
Share transactions - net increase (decrease)	(284,925)	(294,835)
Total increase (decrease) in net assets	(284,851)	(294,766)

Net Assets
Beginning of period	2,601,251	2,896,017
End of period (including distributions in excess of net investment income of $87 and distributions in excess of net investment income of $116, respectively)	$ 2,316,400	$ 2,601,251

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights - Fidelity Money Market Fund

Years ended April 30,	2015	2014	2013	2012	2011
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Income from Investment Operations
Net investment income (loss)^C	-	-	-	-	-
Net realized and unrealized gain (loss)^C	-	-	-	-	-
Total from investment operations^C	-	-	-	-	-
Distributions from net investment income^C	-	-	-	-	-
Distributions from net realized gain	-	-	-	-	-^C
Total distributions^C	-	-	-	-	-
Net asset value, end of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Total Return^A	.01%	.01%	.01%	.01%	.03%
Ratios to Average Net Assets^B
Expenses before reductions	.42%	.42%	.42%	.42%	.42%
Expenses net of fee waivers, if any	.26%	.25%	.36%	.37%	.41%
Expenses net of all reductions	.26%	.25%	.36%	.37%	.41%
Net investment income (loss)	.01%	.01%	.01%	.01%	.03%
Supplemental Data
Net assets, end of period (in millions)	$ 2,316	$ 2,601	$ 2,896	$ 3,388	$ 4,197

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

^B Expense ratios reflect operating expenses of the class. Expenses before reductions do not reflect amounts reimbursed or waived or reductions from expense offset arrangements and do not represent the amount paid by the class during periods when reimbursements, waivers or reductions occur. Expenses net of fee waivers reflect expenses after reimbursement and waivers but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the class.

^C Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights - Premium Class

Year ended April 30,	2015 ^D
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00
Income from Investment Operations
Net investment income (loss)^F	-
Distributions from net investment income^F	-
Net asset value, end of period	$ 1.00
Total Return ^{B, C}	-%
Ratios to Average Net Assets^E
Expenses before reductions	.37% ^A
Expenses net of fee waivers, if any	.28% ^A
Expenses net of all reductions	.28% ^A
Net investment income (loss)	.01% ^A
Supplemental Data
Net assets, end of period (in millions)	$ 1

^A Annualized

^B Total returns for periods of less than one year are not annualized.

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

^D For the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

^E Expense ratios reflect operating expenses of the class. Expenses before reductions do not reflect amounts reimbursed or waived or reductions from expense offset arrangements and do not represent the amount paid by the class during periods when reimbursements, waivers or reductions occur. Expense ratios before reductions for start-up periods may not be representative of longer-term operating periods. Expenses net of fee waivers reflect expenses after reimbursement and waivers but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the class.

^F Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Notes to Financial Statements

For the period ended April 30, 2015

(Amounts in thousands except percentages)

1. Organization.

Fidelity Money Market Fund (the Fund) is a fund of Fidelity Hereford Street Trust (the Trust) and is authorized to issue an unlimited number of shares. 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. The Fund commenced sale of Premium Class shares on April 6, 2015. The Fund offers Fidelity Money Market Fund and Premium Class shares, each of which has equal rights as to assets and voting privileges. Each class has exclusive voting rights with respect to matters that affect that class.

2. Significant Accounting Policies.

Security Valuation. 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 - 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)

Annual Report

2. Significant Accounting Policies - continued

Class Allocations and Expenses. Investment income, realized and unrealized capital gains and losses, common expenses of the Fund, and certain fund-level expense reductions, if any, are allocated daily on a pro-rata basis to each class based on the relative net assets of each class to the total net assets of the Fund. Each class differs with respect to transfer agent fees incurred. Certain expense reductions may also differ by class. For the reporting period, the allocated portion of income and expenses to each class as a percent of its average net assets may vary due to the timing of recording these transactions in relation to fluctuating net assets of the classes. 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. Expense estimates are accrued in the period to which they relate and adjustments are made when actual amounts are known.

Deferred Trustee Compensation. Under a Deferred Compensation Plan (the Plan), independent Trustees may elect to defer receipt of a portion of their annual compensation. Deferred amounts are invested in a cross-section of Fidelity funds, are marked-to-market and remain in the Fund until distributed in accordance with the Plan. The investment of deferred amounts and the offsetting payable to the Trustees are included in the accompanying Statement of Assets and Liabilities.

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. During the period, the Fund incurred an excise tax liability on undistributed net investment income and undistributed short-term capital gain which is included in Miscellaneous expense on the Statement of Operations. As of April 30, 2015, the Fund did not have any unrecognized tax benefits in the financial statements; nor is the Fund aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months. 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.

Dividends 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 dividends and capital gain distributions are declared separately for each class. Income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP. In addition, the Fund claimed

Annual Report

Notes to Financial Statements - continued

(Amounts in thousands except percentages)

2. Significant Accounting Policies - continued

Income Tax Information and Distributions to Shareholders - continued

a portion of the payment made to redeeming shareholders as a distribution for income tax purposes.

Book-tax differences are primarily due to deferred trustees compensation.

The federal tax cost of investment securities and unrealized appreciation (depreciation) as of period end were as follows:

Gross unrealized appreciation	$ -
Gross unrealized depreciation	-
Net unrealized appreciation (depreciation) on securities	$ -

Tax Cost	$ 2,314,474

The tax-based components of distributable earnings as of period end were as follows:

Undistributed ordinary income

$ 97

The tax character of distributions paid was as follows:

	April 30, 2015	April 30, 2014
Ordinary Income	$ 249	$ 311

Annual Report

2. Significant Accounting Policies - continued

Restricted Securities. The Fund may invest in securities that are subject to legal or contractual restrictions on resale. These securities generally may be resold in transactions exempt from registration or to the public if the securities are registered. Disposal of these securities may involve time-consuming negotiations and expense, and prompt sale at an acceptable price may be difficult. Information regarding restricted securities is included at the end of the Fund's Schedule of Investments.

Annual Report

Notes to Financial Statements - continued

(Amounts in thousands except percentages)

3. Fees and Other Transactions with Affiliates.

Management Fee and Expense Contract. Pursuant to the management contract and separate expense contract approved by the Board of Trustees effective February 1, 2015, Fidelity Management & Research Company (the investment adviser) and its affiliates provide the Fund with investment management related services for which the Fund pays a monthly management fee that is based on an annual rate of .25% of the Fund's average net assets. Under the management contract, the Fund is responsible for paying other operating expenses such as pricing and bookkeeping, custody, audit, transfer agent and distribution and service plan fees. Under the expense contract, total expenses of the Fidelity Money Market Fund are limited to an annual rate of .42% of the class' average net assets, with certain exceptions.

Prior to February 1, 2015, there was no expense contract in place and under the management contract, the management fee was based on an annual rate of .42% and the investment adviser paid all other operating expenses. For the reporting period, the Fund's total annual management fee rate was .38% of the Fund's average net assets.

Transfer Agent Fees. Fidelity Investments Institutional Operations Company, Inc. (FIIOC), an affiliate of the investment adviser, is the transfer, dividend disbursing and shareholder servicing agent for each class of the Fund. FIIOC receives asset-based fees with respect to each account. FIIOC pays for typesetting, printing and mailing of shareholder reports, except proxy statements. Premium class pays a transfer agent fee equal to an annual rate of .10% of class-level average net assets.

Under the expense contract, Fidelity Money Market Fund will pay a portion of the transfer agent fee at an annual rate of up to .17% of class-level average net assets.

For the period, transfer agent fees for each class were as follows:

	Amount	% of Class-Level Average Net Assets
Fidelity Money Market Fund	$ 903	.15*
Premium Class	-**	.10*

* Annualized

** Amount represents twenty-six dollars.

During the period, the investment adviser or its affiliates waived a portion of these fees.

Accounting Fees. Fidelity Service Company, Inc. (FSC), an affiliate of the investment adviser, maintains the Fund's accounting records. The fee is based on the level of average net assets for each month.

Annual Report

4. Expense Reductions.

Effective April 6, 2015, the investment adviser contractually agreed to reimburse Premium Class to the extent annual operating expenses exceeded .30% of average net assets. This reimbursement will remain in place through June 30, 2019. Some expenses, for example interest expense, are excluded from this reimbursement. During the period this reimbursement reduced Premium Class' expenses by eighteen dollars.

Additionally, the investment adviser or its affiliates voluntarily agreed to waive certain fees in order to maintain a minimum annualized yield of .01%. Such arrangements may be discontinued by the investment adviser at any time. For the period, the amount of the waiver for each class was as follows:

Fidelity Money Market Fund	$ 4,044
Premium Class	-**
	$ 4,044

** Amount represents four dollars.

In addition, through arrangements with the Fund's custodian, credits realized as a result of uninvested cash balances were used to reduce the Fund's expenses. During the period, these credits reduced the Fund's custody expenses by three hundred and twenty two dollars.

In addition, the investment adviser reimbursed a portion of the Fund's operating expenses during the period in the amount of $5.

5. Distributions to Shareholders.

Distributions to shareholders of each class were as follows:

Years ended April 30,	2015^A	2014
From net investment income
Fidelity Money Market Fund	$ 249	$ 311
Premium Class	-*	$ -
Total	$ 249	$ 311

^A Distributions for Premium Class are for the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

* Amount represents three dollars.

Annual Report

Notes to Financial Statements - continued

(Amounts in thousands except percentages)

6. Share Transactions.

Share transactions for each class of shares at a $1.00 per share were as follows and may contain automatic conversions between classes or exchanges between funds:

Years ended April 30,	2015^A	2014
Fidelity Money Market Fund Shares sold	$ 1,037,698	1,241,131
Reinvestment of distributions	236	295
Shares redeemed	(1,323,630)	(1,536,261)
Net increase (decrease)	(285,696)	(294,835)
Premium Class Shares sold	771	-
Reinvestment of distributions	-	-
Shares redeemed	-	-
Net increase (decrease)	771	-

^A Share transactions for Premium Class are for the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

7. Proposed Reorganization.

The Board of Trustees of the Fund approved an Agreement and Plan of Reorganization (the Agreement) between the Fund and Money Market Portfolio. Pursuant to the Agreement, the Fund will acquire all the assets and assume all the liabilities of the Money Market Portfolio. The reorganization will be accomplished by an exchange of Premium shares of the Fund for shares of Money Market Portfolio at a net asset value of $1.00 on the date the reorganization is effective. The reorganization provides shareholders of Money Market Portfolio access to a larger portfolio with a similar investment objective.

The Money Market Portfolio shareholders approved the reorganization which is expected to become effective on or about November 6, 2015. The reorganization is expected to qualify as a tax-free transaction for federal income tax purposes with no gain or loss recognized by the funds or their shareholders.

8. Other.

Annual Report

Report of Independent Registered Public Accounting Firm

To the Trustees of Fidelity Hereford Street Trust and the Shareholders of Fidelity Money Market Fund:

In our opinion, the accompanying statement of assets and liabilities, including the schedule of investments, and the related statements of operations and of changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Fidelity Money Market Fund (a fund of Fidelity Hereford Street Trust) at April 30, 2015, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended and the financial highlights for each of the periods indicated, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements") are the responsibility of the Fidelity Money Market Fund's management. Our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at April 30, 2015 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion.

PricewaterhouseCoopers LLP

Boston, Massachusetts

June 19, 2015

Annual Report

Trustees and Officers

Annual Report

Trustees and Officers - continued

Annual Report

The fund's Statement of Additional Information (SAI) includes more information about the Trustees. To request a free copy, call Fidelity at 1-800-544-8544.

Interested Trustee*:

Correspondence intended for the Trustee who is an interested person may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Abigail P. Johnson (1961)
Year of Election or Appointment: 2009 Trustee Chairman of the Board of Trustees
	Ms. Johnson also serves as Trustee of other Fidelity funds. Ms. Johnson serves as President (2013-present) and Chief Executive Officer (2014-present) of FMR LLC (diversified financial services company), President of Fidelity Financial Services (2012-present) and President of Personal, Workplace and Institutional Services (2005-present). Ms. Johnson is Chairman and Director of FMR Co., Inc. (investment adviser firm, 2011-present), Chairman and Director of FMR (investment adviser firm, 2011-present), and the Vice Chairman and Director (2007-present) of FMR LLC. Previously, Ms. Johnson served as President and a Director of FMR (2001-2005), a Trustee of other investment companies advised by FMR, Fidelity Investments Money Management, Inc. (investment adviser firm), and FMR Co., Inc. (2001-2005), Senior Vice President of the Fidelity funds (2001-2005), and managed a number of Fidelity funds. Ms. Abigail P. Johnson and Mr. Arthur E. Johnson are not related.

Annual Report

Trustees and Officers - continued

* Trustee has been determined to be an "Interested Trustee" by virtue of, among other things, her affiliation with the trust or various entities under common control with FMR.

Independent Trustees:

Correspondence intended for each Independent Trustee (that is, the Trustees other than the Interested Trustee) may be sent to Fidelity Investments, P.O. Box 55235, Boston, Massachusetts 02205-5235.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Elizabeth S. Acton (1951)
Year of Election or Appointment: 2013 Trustee
	Ms. Acton also serves as Trustee or Member of the Advisory Board of other Fidelity funds. Prior to her retirement in April 2012, Ms. Acton was Executive Vice President, Finance (2011-2012), Executive Vice President, Chief Financial Officer (2002-2011), and Treasurer (2004-2005) of Comerica Incorporated (financial services). Prior to joining Comerica, Ms. Acton held a variety of positions at Ford Motor Company (1983-2002), including Vice President and Treasurer (2000-2002) and Executive Vice President and Chief Financial Officer of Ford Motor Credit Company (1998-2000). Ms. Acton currently serves as a member of the Board of Directors and Audit and Finance Committees of Beazer Homes USA, Inc. (homebuilding, 2012-present).
John Engler (1948)
Year of Election or Appointment: 2014 Trustee
	Mr. Engler also serves as Trustee or Member of the Advisory Board of other Fidelity funds. He serves as president of the Business Roundtable (2011-present), and on the board of directors/trustees for Universal Forest Products (manufacturer and distributor of wood and wood-alternative products, 2003-present), K12 Inc. (technology-based education company, 2012-present), and the Annie E. Casey Foundation (2004-present). Previously, Mr. Engler served as a trustee of The Munder Funds (2003-2014), president and CEO of the National Association of Manufacturers (2004-2011) and as governor of Michigan (1991-2003). He is a past chairman of the National Governors Association.
Albert R. Gamper, Jr. (1942)
Year of Election or Appointment: 2006 Trustee Chairman of the Independent Trustees
	Mr. Gamper also serves as Trustee of other Fidelity funds. Prior to his retirement in December 2004, Mr. Gamper served as Chairman of the Board of CIT Group Inc. (commercial finance). During his tenure with CIT Group Inc. Mr. Gamper served in numerous senior management positions, including Chairman (1987-1989; 1999-2001; 2002-2004), Chief Executive Officer (1987-2004), and President (2002-2003). Mr. Gamper currently serves as a member of the Board of Directors of Public Service Enterprise Group (utilities, 2000-present), and Member of the Board of Trustees of Barnabas Health Care System (1997-present). Previously, Mr. Gamper served as Vice Chairman of the Independent Trustees of certain Fidelity funds (2011-2012) and as Chairman of the Board of Governors, Rutgers University (2004-2007).
Robert F. Gartland (1951)
Year of Election or Appointment: 2010 Trustee
	Mr. Gartland also serves as Trustee of other Fidelity funds. Mr. Gartland is Chairman and an investor in Gartland and Mellina Group Corp. (consulting, 2009-present). Previously, Mr. Gartland served as a partner and investor of Vietnam Partners LLC (investments and consulting, 2008-2011). Prior to his retirement, Mr. Gartland held a variety of positions at Morgan Stanley (financial services, 1979-2007) including Managing Director (1987-2007).
Arthur E. Johnson (1947)
Year of Election or Appointment: 2008 Trustee
	Mr. Johnson also serves as Trustee of other Fidelity funds. Mr. Johnson serves as a member of the Board of Directors of Eaton Corporation plc (diversified power management, 2009-present), AGL Resources, Inc. (holding company, 2002-present) and Booz Allen Hamilton (management consulting, 2011-present). Prior to his retirement, Mr. Johnson served as Senior Vice President of Corporate Strategic Development of Lockheed Martin Corporation (defense contractor, 1999-2009). He previously served on the Board of Directors of IKON Office Solutions, Inc. (1999-2008) and Delta Airlines (2005-2007). Mr. Arthur E. Johnson is not related to Ms. Abigail P. Johnson.
Michael E. Kenneally (1954)
Year of Election or Appointment: 2009 Trustee
	Mr. Kenneally also serves as Trustee of other Fidelity funds. Mr. Kenneally served as a Member of the Advisory Board for certain Fidelity funds before joining the Board of Trustees (2008-2009). Prior to his retirement, Mr. Kenneally served as Chairman and Global Chief Executive Officer of Credit Suisse Asset Management. Before joining Credit Suisse, he was an Executive Vice President and Chief Investment Officer for Bank of America Corporation. Earlier roles at Bank of America included Director of Research, Senior Portfolio Manager and Research Analyst, and Mr. Kenneally was awarded the Chartered Financial Analyst (CFA) designation in 1991.
James H. Keyes (1940)
Year of Election or Appointment: 2007 Trustee
	Mr. Keyes also serves as Trustee of other Fidelity funds. Mr. Keyes serves as a member of the Board and Non-Executive Chairman of Navistar International Corporation (manufacture and sale of trucks, buses, and diesel engines, since 2002). Previously, Mr. Keyes served as a member of the Board of Pitney Bowes, Inc. (integrated mail, messaging, and document management solutions, 1998-2013). Prior to his retirement, Mr. Keyes served as Chairman (1993-2002) and Chief Executive Officer (1988-2002) of Johnson Controls (automotive, building, and energy) and as a member of the Board of LSI Logic Corporation (semiconductor technologies, 1984-2008).
Marie L. Knowles (1946)
Year of Election or Appointment: 2001 Trustee Vice Chairman of the Independent Trustees
	Ms. Knowles also serves as Trustee of other Fidelity funds. Prior to Ms. Knowles' retirement in June 2000, she served as Executive Vice President and Chief Financial Officer of Atlantic Richfield Company (ARCO) (diversified energy, 1996-2000). From 1993 to 1996, she was a Senior Vice President of ARCO and President of ARCO Transportation Company. She served as a Director of ARCO from 1996 to 1998. Ms. Knowles currently serves as a Director and Chairman of the Audit Committee of McKesson Corporation (healthcare service, since 2002). Ms. Knowles is a member of the Board of the Catalina Island Conservancy and of the Santa Catalina Island Company (2009-present). She also serves as a member of the Advisory Board for the School of Engineering of the University of Southern California. Previously, Ms. Knowles served as a Director of Phelps Dodge Corporation (copper mining and manufacturing, 1994-2007), URS Corporation (engineering and construction, 2000-2003) and America West (airline, 1999-2002).

Annual Report

Trustees and Officers - continued

Advisory Board Member and Officers:

Correspondence intended for each officer and Geoffrey A. von Kuhn may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210. Officers appear below in alphabetical order.

Name, Year of Birth; Principal Occupation
Geoffrey A. von Kuhn (1951)
Year of Election or Appointment: 2015 Member of the Advisory Board
	Mr. von Kuhn also serves as a Trustee or Member of the Advisory Board of other Fidelity funds. Mr. von Kuhn is Chief Administrative Officer for FMR LLC (diversified financial services company, 2013-present), a Director of Pembroke Real Estate, Inc. (2009-present), and a Director of Discovery Natural Resources LLC (2012-present). Previously, Mr. von Kuhn was a managing director of Crosby Group (private wealth management company, 2007-2013), a member of the management committee and senior executive in the Wealth Management Group of AmSouth Bank (2001-2006), and head of the U.S. private bank at Citigroup (2000-2001).
Elizabeth Paige Baumann (1968)
Year of Election or Appointment: 2012 Anti-Money Laundering (AML) Officer
	Ms. Baumann also serves as AML Officer of other funds. She is Chief AML Officer of FMR LLC (diversified financial services company, 2012-present) and is an employee of Fidelity Investments. Previously, Ms. Baumann served as Vice President and Deputy Anti-Money Laundering Officer (2007-2012).
Marc Bryant (1966)
Year of Election or Appointment: 2013 Assistant Secretary
	Mr. Bryant also serves as an officer of other funds. He is Senior Vice President and Deputy General Counsel of FMR LLC (diversified financial services company). Previously, Mr. Bryant served as Secretary and Chief Legal Officer of Fidelity Rutland Square Trust II (2010-2014). Prior to joining Fidelity Investments, Mr. Bryant served as a Senior Vice President and the Head of Global Retail Legal for AllianceBernstein L.P. (2006-2010), and as the General Counsel for ProFund Advisors LLC (2001-2006).
Jonathan Davis (1968)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Davis also serves as Assistant Treasurer of other funds. Mr. Davis is an employee of Fidelity Investments. Previously, Mr. Davis served as Vice President and Associate General Counsel of FMR LLC (diversified financial services company, 2003-2010).
Adrien E. Deberghes (1967)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Deberghes also serves as an officer of other funds. He is an employee of Fidelity Investments (2008-present). Prior to joining Fidelity Investments, Mr. Deberghes was Senior Vice President of Mutual Fund Administration at State Street Corporation (2007-2008), Senior Director of Mutual Fund Administration at Investors Bank & Trust (2005-2007), and Director of Finance for Dunkin' Brands (2000-2005).
Stephanie J. Dorsey (1969)
Year of Election or Appointment: 2013 President and Treasurer
	Ms. Dorsey also serves as an officer of other funds. She is an employee of Fidelity Investments (2008-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Dorsey served as Treasurer (2004-2008) of the JPMorgan Mutual Funds and Vice President (2004-2008) of JPMorgan Chase Bank.
Howard J. Galligan III (1966)
Year of Election or Appointment: 2014 Chief Financial Officer
	Mr. Galligan also serves as Chief Financial Officer of other funds. Mr. Galligan serves as President of Fidelity Pricing and Cash Management Services (FPCMS) (2014-present) and as a Director of Strategic Advisers, Inc. (investment adviser firm, 2008-present). Previously, Mr. Galligan served as Chief Administrative Officer of Asset Management (2011-2014) and Chief Operating Officer and Senior Vice President of Investment Support for Strategic Advisers, Inc. (2003-2011).
Scott C. Goebel (1968)
Year of Election or Appointment: 2008 Secretary and Chief Legal Officer (CLO)
	Mr. Goebel serves as Secretary and CLO of other funds. Mr. Goebel also serves as Secretary of Fidelity SelectCo, LLC (investment adviser firm, 2013-present), Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2010-present) and Fidelity Research and Analysis Company (FRAC) (investment adviser firm, 2010-present); General Counsel, Secretary, and Senior Vice President of FMR (investment adviser firm, 2008-present) and FMR Co., Inc. (investment adviser firm, 2008-present); Chief Legal Officer of Fidelity Management & Research (Hong Kong) Limited (investment adviser firm, 2008-present); and Assistant Secretary of Fidelity Management & Research (Japan) Limited (investment adviser firm, 2008-present) and FMR Investment Management (U.K.) Limited (investment adviser firm, 2008-present). Previously, Mr. Goebel served as Secretary and CLO of other Fidelity funds (2008-2013), Assistant Secretary of FIMM (2008-2010), FRAC (2008-2010), and certain funds (2007-2008); and as Vice President and Secretary of Fidelity Distributors Corporation (FDC) (2005-2007). Mr. Goebel has been employed by FMR LLC (diversified financial services company) or an affiliate since 2001.
Chris Maher (1972)
Year of Election or Appointment: 2013 Assistant Treasurer
	Mr. Maher serves as Assistant Treasurer of other funds. Mr. Maher is Vice President of Valuation Oversight and is an employee of Fidelity Investments. Previously, Mr. Maher served as Vice President of Asset Management Compliance (2013), Vice President of the Program Management Group of FMR (investment adviser firm, 2010-2013), and Vice President of Valuation Oversight (2008-2010).
Nancy D. Prior (1967)
Year of Election or Appointment: 2014 Vice President
	Ms. Prior also serves as Vice President of other funds. Ms. Prior serves as a Director of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2014-present), President, Fixed Income (2014-present), Vice Chairman of Pyramis Global Advisors, LLC (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2002-present). Previously, Ms. Prior served as Vice President of Fidelity's Money Market Funds (2012-2014), President, Money Market and Short Duration Bond of FMR (investment adviser firm, 2013-2014), President, Money Market Group of FMR (2011-2014), Managing Director of Research (2009-2011), Senior Vice President and Deputy General Counsel (2007-2009), and Assistant Secretary of other Fidelity funds (2008-2009).
Kenneth B. Robins (1969)
Year of Election or Appointment: 2009 Assistant Treasurer
	Mr. Robins also serves as an officer of other funds. Mr. Robins serves as Executive Vice President of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2013-present) and is an employee of Fidelity Investments (2004-present). Previously, Mr. Robins served in other fund officer roles.
Stephen Sadoski (1971)
Year of Election or Appointment: 2013 Deputy Treasurer
	Mr. Sadoski also serves as Deputy Treasurer of other funds. He is an employee of Fidelity Investments (2012-present) and has served in another fund officer role. Prior to joining Fidelity Investments, Mr. Sadoski served as an assistant chief accountant in the Division of Investment Management of the Securities and Exchange Commission (SEC) (2009-2012) and as a senior manager at Deloitte & Touche LLP (1997-2009).
Stacie M. Smith (1974)
Year of Election or Appointment: 2013 Assistant Treasurer
	Ms. Smith also serves as an officer of other funds. She is an employee of Fidelity Investments (2009-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Smith served as Senior Audit Manager of Ernst & Young LLP (1996-2009).
Renee Stagnone (1975)
Year of Election or Appointment: 2013 Deputy Treasurer
	Ms. Stagnone also serves as Deputy Treasurer of other funds. Ms. Stagnone is an employee of Fidelity Investments.
Michael H. Whitaker (1967)
Year of Election or Appointment: 2008 Chief Compliance Officer
	Mr. Whitaker also serves as Chief Compliance Officer of other funds. Mr. Whitaker also serves as Compliance Officer of FMR Co., Inc. (investment adviser firm, 2014-present), FMR (investment adviser firm, 2014-present), Fidelity Investments Money Management, Inc. (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2007-present). Prior to joining Fidelity Investments, Mr. Whitaker worked at MFS Investment Management where he served as Senior Vice President and Chief Compliance Officer (2004-2006), and Assistant General Counsel.
Joseph F. Zambello (1957)
Year of Election or Appointment: 2011 Deputy Treasurer
	Mr. Zambello also serves as Deputy Treasurer of other funds. Mr. Zambello is an employee of Fidelity Investments. Previously, Mr. Zambello served as Vice President of the Program Management Group of FMR (investment adviser firm, 2009-2011) and Vice President of the Transfer Agent Oversight Group (2005-2009).

Annual Report

Distributions (Unaudited)

The fund hereby designates as a capital gain dividend with respect to the taxable year ended April 30, 2015, $4,520, or, if subsequently determined to be different, the net capital gain of such year.

A total of 2.84% of the dividends distributed during the fiscal year was derived from interest on U.S. Government securities which is generally exempt from state income tax.

The fund designates $54,383 of distributions paid during the period January 1, 2015 to April 30, 2015 as qualifying to be taxed as interest-related dividends for nonresident alien shareholders.

The fund will notify shareholders in January 2016 of amounts for use in preparing 2015 income tax returns.

Annual Report

Board Approval of Investment Advisory Contracts and Management Fees

Fidelity Money Market Fund

On January 14, 2015, the Board of Trustees, including the Independent Trustees (together, the Board), voted to approve an amended management contract (the Amended Contract) for the fund. The Amended Contract lowers the fund's management fee from 42 basis points to 25 basis points of the fund's average daily net assets. The Board, assisted by the advice of fund counsel and Independent Trustees' counsel, considered a broad range of information.

Nature, Extent, and Quality of Services Provided. The Board considered the staffing within the investment adviser, Fidelity Management & Research Company (FMR), and sub-advisers, including the backgrounds of the fund's investment personnel, and also considered the fund's investment objective, strategies, and related investment philosophy.

Shareholder and Administrative Services. The Board considered the nature, extent, quality, and cost of advisory, administrative, and shareholder services to be performed by FMR and its affiliates under the Amended Contract and under separate agreements covering transfer agency and pricing and bookkeeping.

Investment Performance. The Board noted that the approval of the Amended Contract would not change the fund's portfolio manager, the investment processes, the level or nature of services provided, the resources and personnel allocated, or its trading and compliance operations.

Based on its review, the Board concluded that the nature, extent, and quality of the services provided to the fund should benefit the fund's shareholders.

Competitiveness of Management Fee and Total Expense Ratio. The Board considered that, under the fund's existing management contract, the fund paid an all-inclusive management fee, whereby FMR was responsible for payment of the fund's expenses, with certain limited exceptions. In approving the Amended Contract, the Board considered that FMR will no longer be required to pay non-advisory expenses (such as transfer agency, custody, pricing and bookkeeping, legal, and audit fees). The Board also considered that the Amended Contract reduces the fund's management fee from 42 basis points to 25 basis points of the fund's average daily assets. The Board noted that the new lower management fee rate would have ranked the fund's management fee below the median of its competitors based on competitive data provided to the Board in connection with its annual renewal of the fund's advisory contracts in September 2014.

In reviewing the fund's total expenses, the Board considered the fund's management fee as well as the fund's non-advisory expenses, such as transfer agent fees. The Board approved changes (effective February 1, 2015) in the contractual arrangements for the fund that (i) set the transfer agent fee at 20 basis points for its retail class, and (ii) limit total expenses, with certain limited exceptions, to 42 basis points pursuant to a new expense contract. The Board noted that total expenses already were limited to 42 basis points under the fund's existing management contract, and that going forward, under the new expense contract, total expenses of the fund's existing class of shareholders may not exceed 42 basis points without Board and shareholder approval. The Board also noted that the projected total expenses of the fund would have ranked below the median of its competitors based on competitive data provided to the Board in connection with its annual renewal of the fund's advisory contracts in September 2014.

Annual Report

Board Approval of Investment Advisory Contracts and
Management Fees - continued

Based on its review, the Board concluded that the fund's management fee and total expenses were reasonable in light of the services that the fund receives and the other factors considered.

Costs of the Services and Profitability. The Board noted that it considered the revenues earned and the expenses incurred by Fidelity in conducting the business of developing, marketing, distributing, managing, administering and servicing the fund and servicing the fund's shareholders in connection with its annual renewal of the fund's advisory contracts in September 2014. Because the new arrangements reduce the management fee and limit total expenses to the level at which they previously had been capped, the Board concluded that it did not consider additional data regarding the impact of the new arrangements on Fidelity's costs of services or profitability to be a significant factor in approving the Amended Contract. In connection with its future renewal of the fund's advisory contracts, the Board will consider Fidelity's costs of services and profitability.

Economies of Scale. The Board noted that it previously received and reviewed information regarding whether there have been economies of scale in respect of the management of the fund, whether the fund has appropriately benefited from any such economies of scale, and whether there is potential for realization of any further economies of scale in connection with its annual renewal of the fund's advisory contracts in September 2014. Because the new arrangements reduce the management fee and limit total expenses to the level at which they previously had been capped, the Board concluded that it did not consider additional data regarding economies of scale to be a significant factor in approving the Amended Contract. In connection with its future renewal of the fund's advisory contracts, the Board will consider economies of scale.

Based on its evaluation of all of the conclusions noted above, and after considering all factors it believed relevant, the Board ultimately concluded that the advisory fee structure is fair and reasonable, and that the Amended Contract should be approved.

Annual Report

Investment Adviser

Fidelity Management & Research Company

Boston, MA

Investment Sub-Advisers

Fidelity Investments
Money Management, Inc.

Fidelity Management & Research
(Hong Kong) Limited

Fidelity Management & Research
(Japan) Limited

FMR Investment Management
U.K. Limited

General Distributor

Fidelity Distributors Corporation

Smithfield, RI

Transfer and Service Agents

Fidelity Investments Institutional
Operations Company, Inc.

Boston, MA

Fidelity Service Company, Inc.

Boston, MA

Custodian

JPMorgan Chase Bank

New York, NY

The Fidelity Telephone Connection

Mutual Fund 24-Hour Service

Exchanges/Redemptions
and Account Assistance 1-800-544-6666

Product Information 1-800-544-6666

Retirement Accounts 1-800-544-4774
(8 a.m. - 9 p.m.)

TDD Service 1-800-544-0118
for the deaf and hearing impaired
(9 a.m. - 9 p.m. Eastern time)

Fidelity Automated Service
Telephone (FAST®) for283
1-800-544-5555

Automated line for quickest service

(Fidelity Investment logo)(registered trademark)
Corporate Headquarters
245 Summer St., Boston, MA 02210
www.fidelity.com

SPM-ANN-0615
1.703534.117

Fidelity® Government
Money Market
Fund

Annual Report

April 30, 2015

(Fidelity Cover Art)

Shareholder Expense Example	(Click Here)	An example of shareholder expenses.
Investment Changes/Performance	(Click Here)	A summary of major shifts in the fund's investments over the past six months and one year.
Investments	(Click Here)	A complete list of the fund's investments.
Financial Statements	(Click Here)	Statements of assets and liabilities, operations, and changes in net assets, as well as financial highlights.
Notes	(Click Here)	Notes to the financial statements.
Report of Independent Registered Public Accounting Firm	(Click Here)
Trustees and Officers	(Click Here)
Distributions	(Click Here)
Board Approval of Investment Advisory Contracts and Management Fees	(Click Here)

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 for Fidelity® Government Money Market Fund or Premium Class of the fund or 1-877-208-0098 for Capital Reserves Class or Daily Money Class of the fund 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.

Annual Report

Shareholder Expense Example

As a shareholder of the Fund, you incur two types of costs: (1) transaction costs and (2) ongoing costs, including management fees, distribution and/or service (12b-1) fees and other Fund expenses. This Example is intended to help you understand your ongoing costs (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds.

The actual expense Example is based on an investment of $1,000 invested at the beginning of the period and held for the entire period (November 1, 2014 to April 30, 2015) for Fidelity Government Money Market Fund, and for the period (April 6, 2015 to April 30, 2015) for Capital Reserves Class, Daily Money Class, and Premium Class. The hypothetical expense Example is based on an investment of $1,000 invested for one-half year period (November 1, 2014 to April 30, 2015).

Actual Expenses

Hypothetical Example for Comparison Purposes

Annual Report

	Annualized Expense Ratio^B	Beginning Account Value	Ending Account Value April 30, 2015	Expenses Paid During Period
Capital Reserves Class	.13%
Actual		$ 1,000.00	$ 1,000.01	$ .09^C
Hypothetical^A		$ 1,000.00	$ 1,024.15	$ .65^D
Daily Money Class	.13%
Actual		$ 1,000.00	$ 1,000.01	$ .09^C
Hypothetical^A		$ 1,000.00	$ 1,024.15	$ .65^D
Fidelity Government Money Market Fund	.12%
Actual		$ 1,000.00	$ 1,000.05	$ .60^C
Hypothetical^A		$ 1,000.00	$ 1,024.20	$ .60^D
Premium Class	.14%
Actual		$ 1,000.00	$ 1,000.01	$ .10^C
Hypothetical^A		$ 1,000.00	$ 1,024.10	$ .70^D

^A 5% return per year before expenses

^B Annualized expense ratio reflects expenses net of applicable fee waivers.

^C Actual expenses are equal to each Class' annualized expense ratio, multiplied by the average account value over the period, multiplied by 181/365 (to reflect the one-half year period) for Fidelity Government Money Market Fund, and multiplied by 25/365 (to reflect the period April 6, 2015 to April 30, 2015) for Capital Reserves Class, Daily Money Class and Premium Class.

^D Hypothetical expenses are equal to the Class' annualized expense ratio, multiplied by the average value of the period, multiplied by the 181/365 (to reflect the one-half year period).

Annual Report

Investment Changes/Performance (Unaudited)

Effective Maturity Diversification
Days	% of fund's investments 4/30/15	% of fund's investments 10/31/14	% of fund's investments 4/30/14
1 - 7	50.0	55.7	42.5
8 - 30	12.9	17.9	20.3
31 - 60	10.0	7.0	14.0
61 - 90	3.9	2.5	5.0
91 - 180	20.2	3.8	11.4
> 180	3.0	13.1	6.8

Effective maturity is determined in accordance with the requirements of Rule 2a-7 under the Investment Company Act of 1940.

Weighted Average Maturity
	4/30/15	10/31/14	4/30/14
Fidelity Government Money Market Fund	44 Days	52 Days	45 Days
Government Retail Money Market Funds Average *	47 Days	51 Days	49 Days

Weighted Average Life
	4/30/15	10/31/14	4/30/14
Fidelity Government Money Market Fund	87 Days	103 Days	107 Days

* Source: iMoneyNet, Inc.

Annual Report

Asset Allocation (% of fund's net assets)
As of April 30, 2015		As of October 31, 2014
	Treasury Debt 0.7%		Treasury Debt 0.4%
	Government Agency Debt 49.4%		Government Agency Debt 43.7%
	Repurchase Agreements 53.3%		Repurchase Agreements 55.8%
	Net Other Assets (Liabilities)** (3.4)%		Net Other Assets (Liabilities) 0.1%

for312

** Net Other Assets are not included in the pie chart.

Current and Historical Seven-Day Yields

	4/30/15	1/31/15	10/31/14	7/31/14	4/30/14

Capital Reserves Class	0.01%	N/A	N/A	N/A	N/A

Daily Money Class	0.01%	N/A	N/A	N/A	N/A

Fidelity Government Money Market Fund	0.01%	0.01%	0.01%	0.01%	0.01%

Premium Class	0.01%	N/A	N/A	N/A	N/A

Annual Report

Investments April 30, 2015

Showing Percentage of Net Assets

Treasury Debt - 0.7%
		Yield (a)	Principal Amount	Value
U.S. Treasury Obligations - 0.7%
U.S. Treasury Notes
	10/31/15	0.18%	$ 113,000,000
(Cost $113,036,505)				$ 113,036,505
Government Agency Debt - 49.4%

Federal Agencies - 49.4%
Fannie Mae
	8/5/15 to 10/26/15	0.15 to 0.33 (b)	325,690,000	325,923,922
Federal Farm Credit Bank
	8/21/15 to 10/3/16	0.15 to 0.20 (b)	277,425,000	277,448,750
Federal Home Loan Bank
	5/1/15 to 12/23/16	0.11 to 0.35 (b)	6,773,935,000	6,774,098,934
Freddie Mac
	6/26/15 to 1/12/17	0.15 to 0.19 (b)	764,000,000	763,916,236
TOTAL GOVERNMENT AGENCY DEBT (Cost $8,141,387,842)				8,141,387,842

Government Agency Repurchase Agreement - 41.4%
	Maturity Amount
In a joint trading account at:
0.13% dated 4/30/15 due 5/1/15 (Collateralized by U.S. Government Obligations) #	$ 50,000,181		50,000,000
0.14% dated 4/30/15 due 5/1/15 (Collateralized by U.S. Government Obligations) #	1,445,810,688		1,445,805,000
With:
BNP Paribas Securities Corp. at:
0.1%, dated 4/20/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $367,260,929, 0% - 7.63%, 8/15/15 - 4/1/45)	360,063,000		360,000,000
0.11%, dated 4/6/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $326,424,962, 0% - 6.5%, 9/30/15 - 4/20/45)	320,088,978		320,000,000
Citibank NA at 0.09%, dated 4/28/15 due 5/5/15 (Collateralized by U.S. Government Obligations valued at $546,561,622, 0% - 7%, 9/15/15 - 11/15/49)	535,537,372		535,528,000
Government Agency Repurchase Agreement - continued
	Maturity Amount		Value
With: - continued
ING Financial Markets LLC at:
0.1%, dated 3/27/15 due 5/4/15 (Collateralized by U.S. Government Obligations valued at $271,741,481, 3.5% - 4%, 11/1/25 - 1/1/43)	$ 266,415,119		$ 266,387,000
0.11%, dated:
4/7/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $218,100,587, 3.5%, 3/1/42 - 10/1/42)	213,828,599		213,809,000
4/9/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $184,635,828, 2.5% - 7.5%, 10/1/25 - 6/1/44)	181,017,698		181,000,000
4/16/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $109,147,783, 3.5% - 4%, 7/1/26 - 10/1/44)	107,010,462		107,000,000
Merrill Lynch, Pierce, Fenner & Smith at:
0.11%, dated 4/20/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $581,419,542, 1.33% - 4.67%, 11/1/19 - 4/1/45)	570,104,500		570,000,000
0.12%, dated 4/16/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $387,619,380, 1.9% - 5%, 10/1/20 - 5/1/45)	380,077,267		380,000,000
Mitsubishi UFJ Securities (U.S.A.), Inc. at 0.17%, dated:
4/6/15 due 6/5/15 (Collateralized by U.S. Government Obligations valued at $305,016,006, 1.33% - 6.5%, 12/1/21 - 2/1/45)	299,084,717		299,000,000
4/7/15 due 6/8/15 (Collateralized by U.S. Government Obligations valued at $306,034,689, 1.33% - 5.85%, 12/1/21 - 11/1/44)	300,087,833		300,000,000
Mizuho Securities U.S.A., Inc. at 0.18%, dated 1/15/15 due 5/7/15 (Collateralized by U.S. Treasury Obligations valued at $50,970,465, 0% - 5%, 5/15/15 - 2/15/35)	49,907,927		49,878,000
RBC Capital Markets Corp. at:
0.1%, dated 2/2/15 due 5/5/15 (Collateralized by U.S. Government Obligations valued at $251,422,862, 0.48% - 10.5%, 1/15/16 - 5/1/45)	246,411,956		246,349,000
0.13%, dated:
3/13/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $259,140,789, 0.67% - 7.52%, 1/1/17 - 5/1/45)	254,082,550		254,000,000
4/15/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $146,919,794, 2% - 6.5%, 3/1/23 - 5/1/45)	144,047,320		144,000,000
Government Agency Repurchase Agreement - continued
	Maturity Amount		Value
With: - continued
RBC Capital Markets Corp. at:
0.14%, dated 3/26/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $181,585,419, 2.09% - 6%, 9/1/20 - 4/20/45)	$ 178,062,300		$ 178,000,000
Wells Fargo Securities, LLC at:
0.1%, dated:
4/28/15 due 5/5/15 (Collateralized by U.S. Government Obligations valued at $182,080,697, 2.5% - 3.5%, 4/1/30 - 3/1/45)	178,512,471		178,509,000
4/29/15 due 5/6/15 (Collateralized by U.S. Government Obligations valued at $437,807,222, 1.63% - 5.5%, 3/1/25 - 5/1/45)	429,133,344		429,125,000
0.11%, dated 2/4/15 due 5/4/15 (Collateralized by U.S. Government Obligations valued at $152,019,938, 3% - 3.5%, 3/1/45)	149,040,520		149,000,000
0.13%, dated 4/30/15 due 5/7/15 (Collateralized by U.S. Government Obligations valued at $183,600,663, 2.5% - 5%, 4/1/30 - 4/1/45)	180,004,550		180,000,000
TOTAL GOVERNMENT AGENCY REPURCHASE AGREEMENT (Cost $6,837,390,000)		6,837,390,000
Treasury Repurchase Agreement - 11.9%

With Federal Reserve Bank of New York at 0.05%, dated 4/30/15 due 5/1/15 (Collateralized by U.S. Treasury Obligations valued at $1,963,002,728, 4.25%, 5/15/39) (Cost $1,963,000,000)	1,963,002,726		1,963,000,000
TOTAL INVESTMENT PORTFOLIO - 103.4% (Cost $17,054,814,347)		17,054,814,347
NET OTHER ASSETS (LIABILITIES) - (3.4)%		(568,633,509)
NET ASSETS - 100%		$ 16,486,180,838

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) Coupon rates for floating and adjustable rate securities reflect the rates in effect at period end.

# Additional information on each counterparty to the repurchase agreement is as follows:

Repurchase Agreement / Counterparty	Value
$50,000,000 due 5/01/15 at 0.13%
Citibank NA	$ 24,996,876
Merrill Lynch, Pierce, Fenner & Smith, Inc.	4,374,453
Societe Generale	9,998,750
Wachovia Bank NA	10,629,921
	$ 50,000,000
$1,445,805,000 due 5/01/15 at 0.14%
BNY Mellon Capital Markets LLC	$ 291,845,019
Bank of America NA	369,847,234
Merrill Lynch, Pierce, Fenner & Smith, Inc.	19,633,210
Mizuho Securities USA, Inc.	331,642,067
Societe Generale	45,103,321
Wachovia Bank NA	258,614,484
Wells Fargo Securities LLC	129,119,665
	$ 1,445,805,000

Other Information

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements

Statement of Assets and Liabilities

	April 30, 2015

Assets
Investment in securities, at value (including repurchase agreements of $8,800,390,000) - See accompanying schedule: Unaffiliated issuers (cost $17,054,814,347)		$ 17,054,814,347
Receivable for fund shares sold		177,657,422
Interest receivable		2,856,170
Receivable from investment adviser for expense reductions		87
Total assets		17,235,328,026

Liabilities
Payable to custodian bank	$ 84
Payable for investments purchased	558,937,956
Payable for fund shares redeemed	188,314,186
Distributions payable	7,184
Accrued management fee	1,506,370
Other affiliated payables	269,758
Other payables and accrued expenses	111,650
Total liabilities		749,147,188

Net Assets		$ 16,486,180,838
Net Assets consist of:
Paid in capital		$ 16,486,170,888
Distributions in excess of net investment income		(2)
Accumulated undistributed net realized gain (loss) on investments		9,952
Net Assets		$ 16,486,180,838

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements - continued

Statement of Assets and Liabilities - continued

	April 30, 2015

Capital Reserves Class: Net Asset Value, offering price and redemption price per share ($15,826,865 ÷ 15,826,550 shares)		$ 1.00

Daily Money Class: Net Asset Value, offering price and redemption price per share ($8,449,379 ÷ 8,449,213 shares)		$ 1.00

Fidelity Government Money Market Fund: Net Asset Value, offering price and redemption price per share ($16,461,418,583 ÷ 16,461,163,662 shares)		$ 1.00

Premium Class: Net Asset Value, offering price and redemption price per share ($486,011 ÷ 486,001 shares)		$ 1.00

See accompanying notes which are an integral part of the financial statements.

Annual Report

Statement of Operations

	Year ended April 30, 2015

Investment Income
Interest		$ 19,006,940

Expenses
Management fee	$ 58,787,231
Transfer agent fees	6,445,882
Distribution and service plan fees	861
Accounting fees and expenses	268,775
Custodian fees and expenses	18,925
Independent trustees' compensation	67,042
Registration fees	75,966
Audit	13,541
Legal	516
Miscellaneous	3,913
Total expenses before reductions	65,682,652
Expense reductions	(48,238,882)	17,443,770
Net investment income (loss)		1,563,170
Realized and Unrealized Gain (Loss) Net realized gain (loss) on:
Investment securities:
Unaffiliated issuers		24,875
Net increase in net assets resulting from operations		$ 1,588,045

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Statements - continued

Statement of Changes in Net Assets

	Year ended April 30, 2015	Year ended April 30, 2014
Increase (Decrease) in Net Assets
Operations
Net investment income (loss)	$ 1,563,170	$ 1,421,048
Net realized gain (loss)	24,875	65,747
Net increase in net assets resulting from operations	1,588,045	1,486,795
Distributions to shareholders from net investment income	(1,563,142)	(1,419,538)
Share transactions - net increase (decrease)	1,199,783,646	4,367,238,504
Total increase (decrease) in net assets	1,199,808,549	4,367,305,761

Net Assets
Beginning of period	15,286,372,289	10,919,066,528
End of period (including distributions in excess of net investment income of $2 and $0, respectively)	$ 16,486,180,838	$ 15,286,372,289

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights - Capital Reserves Class

Year ended April 30,	2015^D
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00
Income from Investment Operations
Net investment income (loss)^F	-
Distributions from net investment income^F	-
Net asset value, end of period	$ 1.00
Total Return^B,C	-
Ratios to Average Net Assets^E
Expenses before reductions	.99%^A
Expenses net of fee waivers, if any	.13%^A
Expenses net of all reductions	.13%^A
Net investment income (loss)	.01%^A
Supplemental Data
Net assets, end of period (000 omitted)	$ 15,827

^A Annualized

^B Total returns for periods of less than one year are not annualized.

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

^D For the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

^E Expense ratios reflect operating expenses of the class. Expenses before reductions do not reflect amounts reimbursed or waived or reductions from expense offset arrangements and do not represent the amount paid by the class during periods when reimbursements, waivers or reductions occur. Expense ratios before reductions for start-up periods may not be representative of longer-term periods. Expenses net of fee waivers reflect expenses after reimbursement and waivers but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the class.

^F Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights - Daily Money Class

Year ended April 30,	2015^D
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00
Income from Investment Operations
Net investment income (loss)^F	-
Distributions from net investment income^F	-
Net asset value, end of period	$ 1.00
Total Return^B,C	-
Ratios to Average Net Assets^E
Expenses before reductions	.74%^A
Expenses net of fee waivers, if any	.13%^A
Expenses net of all reductions	.13%^A
Net investment income (loss)	.01%^A
Supplemental Data
Net assets, end of period (000 omitted)	$ 8,449

^A Annualized

^B Total returns for periods of less than one year are not annualized.

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

^D For the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

^E Expense ratios reflect operating expenses of the class. Expenses before reductions do not reflect amounts reimbursed or waived or reductions from expense offset arrangements and do not represent the amount paid by the class during periods when reimbursements, waivers or reductions occur. Expense ratios before reductions for start-up periods may not be representative of longer-term periods. Expenses net of fee waivers reflect expenses after reimbursement and waivers but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the class.

^F Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights - Fidelity Government Money Market Fund

Years ended April 30,	2015	2014	2013	2012	2011
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Income from Investment Operations
Net investment income (loss)^C	-	-	-	-	-
Net realized and unrealized gain (loss) ^C	-	-	-	-	-
Total from investment operations^C	-	-	-	-	-
Distributions from net investment income^C	-	-	-	-	-
Distributions from net realized gain	-	-	-	-	-^C
Total distributions^C	-	-	-	-	-
Net asset value, end of period	$ 1.00	$ 1.00	$ 1.00	$ 1.00	$ 1.00
Total Return^A	.01%	.01%	.01%	.01%	.01%
Ratios to Average Net Assets^B
Expenses before reductions	.42%	.42%	.42%	.42%	.42%
Expenses net of fee waivers, if any	.11%	.11%	.19%	.16%	.26%
Expenses net of all reductions	.11%	.11%	.19%	.16%	.26%
Net investment income (loss)	.01%	.01%	.01%	.01%	.01%
Supplemental Data
Net assets, end of period (000 omitted)	$ 16,461,419	$ 15,286,372	$ 10,919,067	$ 2,826,285	$ 583,462

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

^C Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Financial Highlights - Premium Class

Year ended April 30,	2015^D
Selected Per-Share Data
Net asset value, beginning of period	$ 1.00
Income from Investment Operations
Net investment income (loss)^F	-
Distributions from net investment income^F	-
Net asset value, end of period	$ 1.00
Total Return^B,C	-
Ratios to Average Net Assets^E
Expenses before reductions	.37%^A
Expenses net of fee waivers, if any	.14%^A
Expenses net of all reductions	.14%^A
Net investment income (loss)	.02%^A
Supplemental Data
Net assets, end of period (000 omitted)	$ 486

^A Annualized

^B Total returns for periods of less than one year are not annualized.

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

^D For the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

^E Expense ratios reflect operating expenses of the class. Expenses before reductions do not reflect amounts reimbursed or waived or reductions from expense offset arrangements and do not represent the amount paid by the class during periods when reimbursements, waivers or reductions occur. Expense ratios before reductions for start-up periods may not be representative of longer-term periods. Expenses net of fee waivers reflect expenses after reimbursement and waivers but prior to reductions from expense offset arrangements. Expenses net of all reductions represent the net expenses paid by the class.

^F Amount represents less than $.001 per share.

See accompanying notes which are an integral part of the financial statements.

Annual Report

Notes to Financial Statements

For the period ended April 30, 2015

1. Organization.

Fidelity Government Money Market Fund (the Fund) is a fund of Fidelity Hereford Street Trust (the Trust) and is authorized to issue an unlimited number of shares. 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. The Fund commenced sale of Capital Reserves Class, Daily Money Class and Premium Class shares on April 6, 2015. The Fund offers Capital Reserves Class, Daily Money Class, Fidelity Government Money Market Fund and Premium Class shares, each of which has equal rights as to assets and voting privileges. Each class has exclusive voting rights with respect to matters that affect that class.

2. Significant Accounting Policies.

Security Valuation. 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 - 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)

Annual Report

2. Significant Accounting Policies - continued

Investment Transactions and Income. The net asset value 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. Security transactions are accounted for as of trade date. Gains and losses on securities sold are determined on the basis of identified cost. Interest income is accrued as earned and includes coupon interest and amortization of premium and accretion of discount on debt securities as applicable. The principal amount on inflation-indexed securities is periodically adjusted to the rate of inflation and interest is accrued based on the principal amount. The adjustments to principal due to inflation are reflected as increases or decreases to Interest in the accompanying Statement of Operations.

Class Allocations and Expenses. Investment income, realized and unrealized capital gains and losses, common expenses of the Fund, and certain fund-level expense reductions, if any, are allocated daily on a pro-rata basis to each class based on the relative net assets of each class to the total net assets of the Fund. Each class differs with respect to transfer agent and distribution and service plan fees incurred. Certain expense reductions may also differ by class. For the reporting period, the allocated portion of income and expenses to each class as a percent of its average net assets may vary due to the timing of recording these transactions in relation to fluctuating net assets of the classes. 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. 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. As of April 30, 2015, the Fund did not have any unrecognized tax benefits in the financial statements; nor is the Fund aware of any tax positions for which it is reasonably possible that the total amounts of unrecognized tax benefits will significantly change in the next twelve months. 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.

Dividends 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 dividends and capital gain distributions are declared separately for each class. Income and capital gain distributions are determined in accordance with income tax regulations, which may differ from GAAP. In addition, the Fund claimed

Annual Report

Notes to Financial Statements - continued

2. Significant Accounting Policies - continued

Income Tax Information and Distributions to Shareholders - continued

a portion of the payment made to redeeming shareholders as a distribution for income tax purposes.

Book-tax differences are primarily due to deferred trustees compensation.

The federal tax cost of investment securities and unrealized appreciation (depreciation) as of period end were as follows:

Gross unrealized appreciation	$ -
Gross unrealized depreciation	-
Net unrealized appreciation (depreciation) on securities	$ -

Tax Cost	$ 17,054,814,347

The tax-based components of distributable earnings as of period end were as follows:

Undistributed ordinary income

$ 10,934

The tax character of distributions paid was as follows:

	April 30, 2015	April 30, 2014
Ordinary Income	$ 1,563,142	$ 1,419,538

Annual Report

2. Significant Accounting Policies - continued

New Rule Issuance. In July 2014, the U.S. Securities and Exchange Commission issued Final Rule Release No. 33-9616, Money Market Fund Reform; Amendments to Form PF, which amends the rules governing money market funds. The final amendments impose different implementation dates for the changes that certain money market funds will need to make. Management is currently evaluating the implication of these amendments and their impact of the Final Rule to the Money Market Fund's financial statements and related disclosures.

3. Fees and Other Transactions with Affiliates.

Management Fee and Expense Contract. Pursuant to the management contract and separate expense contract approved by the Board of Trustees effective February 1, 2015, Fidelity Management & Research Company (the investment adviser) and its affiliates provide the Fund with investment management related services for which the Fund pays a monthly management fee that is based on an annual rate of .25% of the Fund's average net assets. Under the management contract, the Fund is responsible for paying other operating expenses such as pricing and bookkeeping, custody, audit, transfer agent and distribution and service plan fees. Under the expense contract, total expenses of the Fidelity Government Money Market Fund are limited to an annual rate of .42% of the class' average net assets, with certain exceptions.

Annual Report

Notes to Financial Statements - continued

3. Fees and Other Transactions with Affiliates - continued

Distribution and Service Plan Fees. In accordance with Rule 12b-1 of the 1940 Act, the Fund has adopted separate Distribution and Service Plans for each class of shares. Certain classes pay Fidelity Distributors Corporation (FDC), an affiliate of the investment adviser, separate Distribution and Service Fees, each of which is based on an annual percentage of each class' average net assets. In addition, FDC may pay financial intermediaries for selling shares of the Fund and providing shareholder support services. For the period, the Distribution and Service Fee rates, total fees and amounts retained by FDC were as follows:

	Distribution Fee	Service Fee	Total Fees	Retained by FDC
Capital Reserves Class	.25%	.25%	$ 660	$ 253
Daily Money Class	-%	.25%	201	151

During the period, the investment adviser or its affiliates waived a portion of these fees.

Transfer Agent Fees. Fidelity Investments Institutional Operations Company, Inc. (FIIOC), an affiliate of the investment adviser, is the transfer, dividend disbursing and shareholder servicing agent for each class of the Fund. FIIOC receives asset-based fees with respect to each account. FIIOC pays for typesetting, printing and mailing of shareholder reports, except proxy statements. Each class pays a transfer agent fee equal to an annual rate of .20% of class-level average net assets, with the exception of Premium Class which pays .10% of class-level average net assets.

Under the expense contract, Fidelity Government Money Market Fund will pay a portion of the transfer agent fee at an annual rate of up to .17% of class-level average net assets.

For the period, transfer agent fees for each class were as follows:

	Amount	% of Class-Level Average Net Assets
Capital Reserves Class	$ 264	.20%*
Daily Money Class	161	.20%*
Fidelity Government Money Market Fund	6,445,434	.17%*
Premium Class	23	.10%*

* Annualized

During the period, the investment adviser or its affiliates waived a portion of these fees.

Annual Report

4. Expense Reductions.

Effective April 6, 2015 the investment adviser contractually agreed to reimburse each class to the extent annual operating expenses exceeded certain levels of average net assets as noted in the table below. This reimbursement will remain in place through June 30, 2019. Some expenses, for example interest expense, are excluded from this reimbursement.

The following classes were in reimbursement during the period:

	Expense Limitations	Reimbursement
Capital Reserves Class	.95%	$ 50
Daily Money Class	.70%	27
Premium Class	.32%	10
		$ 87

Fidelity Government Money Market Fund
Capital Reserves Class	$ 1,065
Daily Money Class	450
Fidelity Government Money Market Fund	48,233,741
Premium Class	41

In addition, the investment adviser reimbursed a portion of the Fund's operating expenses during the period in the amount of $283.

Through arrangements with the Fund's custodian, credits realized as a result of uninvested cash balances were used to reduce the Fund's expenses. During the period, these credits reduced the Fund's management fee by $3,215.

5. Distributions to Shareholders.

Distributions to shareholders of each class were as follows:

Years ended April 30,	2015 ^A	2014
From net investment income
Capital Reserves Class	$ 13	$ -
Daily Money Class	8	-
Fidelity Government Money Market Fund	1,563,119	1,419,538
Premium Class	2	-
Total	$ 1,563,142	$ 1,419,538

^A Distributions for Capital Reserves Class, Daily Money Class and Premium Class are for the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

Annual Report

Notes to Financial Statements - continued

6. Share Transactions.

Share transactions for each class of shares at a $1.00 per share were as follows and may contain automatic conversions between classes or exchanges between funds:

Years ended April 30,	2015 ^A	2014
Capital Reserves Class Shares sold	19,789,899	-
Reinvestment of distributions	10	-
Shares redeemed	(3,963,359)	-
Net increase (decrease)	15,826,550	-
Daily Money Class Shares sold	11,907,448	-
Reinvestment of distributions	6	-
Shares redeemed	(3,458,241)	-
Net increase (decrease)	8,449,213	-
Fidelity Government Money Market Fund Shares sold	39,687,229,337	44,571,166,484
Reinvestment of distributions	1,496,725	1,370,129
Shares redeemed	(38,513,704,180)	(40,205,298,109)
Net increase (decrease)	1,175,021,882	4,367,238,504
Premium Class A Shares sold	486,000	-
Reinvestment of distributions	1	-
Shares redeemed	-	-
Net increase (decrease)	486,001	-

^A Share Transactions for Capital Reserves Class, Daily Money Class and Premium Class are for the period April 6, 2015 (commencement of sale of shares) to April 30, 2015.

7. Reorganization.

Subsequent to period end, on May 15, 2015, the Fund acquired all of the assets and assumed all of the liabilities of Government Fund ("Target Fund") pursuant to an Agreement and Plan of Reorganization approved by the Board of Trustees ("the Board") on January 14, 2015. The reorganization was accomplished by an exchange of the corresponding classes of shares of the Fund for each class of the Target Fund at a net asset value of $1.00 on the reorganization date. The reorganization provides shareholders of the Target Fund access to a larger portfolio with a similar investment objective. The reorganization qualified as a tax-free reorganization for federal income tax purposes with no gain or loss recognized to the funds or their shareholders. The Target Fund's net assets of $48,338,877, including securities of $48,366,096, were combined with the Fund's net assets of $16,623,004,431 for total net assets after the reorganization of $16,671,343,308.

Annual Report

8. Proposed Reorganization.

The Board of Trustees of the Fund approved Agreements and Plans of Reorganization (the Agreements) between the Fund and Prime Fund and Fidelity U.S. Government Reserves Fund. Pursuant to the Agreements, the Fund will acquire all the assets and assume all the liabilities of Prime Fund and Fidelity U.S. Government Reserves Fund. The reorganizations will be accomplished by an exchange of each class of shares of Prime Fund and Fidelity U.S. Government Reserves Fund for shares of the corresponding classes of the Fund at a net asset value of $1.00 on the date the reorganization is effective. The reorganizations provide shareholders of Prime Fund and Fidelity U.S. Government Reserves Fund access to a larger portfolio with a similar investment objective.

The Prime Fund and Fidelity U.S. Government Reserves Fund shareholders approved the reorganization which is expected to become effective on or about November 13, 2015 and November 20, 2015, respectively. The reorganizations are expected to qualify as a tax-free transaction for federal income tax purposes with no gain or loss recognized by the funds or their shareholders.

9. Other.

Annual Report

Report of Independent Registered Public Accounting Firm

To the Trustees of Fidelity Hereford Street Trust and the Shareholders of Fidelity Government Money Market Fund:

In our opinion, the accompanying statement of assets and liabilities, including the schedule of investments, and the related statements of operations and of changes in net assets and the financial highlights present fairly, in all material respects, the financial position of Fidelity Government Money Market Fund (a fund of Fidelity Hereford Street Trust) at April 30, 2015, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended and the financial highlights for each of the periods indicated, in conformity with accounting principles generally accepted in the United States of America. These financial statements and financial highlights (hereafter referred to as "financial statements") are the responsibility of the Fidelity Government Money Market Fund's management. Our responsibility is to express an opinion on these financial statements based on our audits. We conducted our audits of these financial statements in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits, which included confirmation of securities at April 30, 2015 by correspondence with the custodian and brokers, provide a reasonable basis for our opinion.

PricewaterhouseCoopers LLP

Boston, Massachusetts

June 19, 2015

Annual Report

Trustees and Officers

Annual Report

Trustees and Officers - continued

The fund's Statements of Additional Information (SAIs) include more information about the Trustees. To request a free copy, call Fidelity at 1-800-544-8544 for Fidelity Government Money Market Fund or Premium Class or 1-877-208-0098 for Capital Reserves Class or Daily Money Class.

Interested Trustee*:

Correspondence intended for the Trustee who is an interested person may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Abigail P. Johnson (1961)
Year of Election or Appointment: 2009 Trustee Chairman of the Board of Trustees
	Ms. Johnson also serves as Trustee of other Fidelity funds. Ms. Johnson serves as President (2013-present) and Chief Executive Officer (2014-present) of FMR LLC (diversified financial services company), President of Fidelity Financial Services (2012-present) and President of Personal, Workplace and Institutional Services (2005-present). Ms. Johnson is Chairman and Director of FMR Co., Inc. (investment adviser firm, 2011-present), Chairman and Director of FMR (investment adviser firm, 2011-present), and the Vice Chairman and Director (2007-present) of FMR LLC. Previously, Ms. Johnson served as President and a Director of FMR (2001-2005), a Trustee of other investment companies advised by FMR, Fidelity Investments Money Management, Inc. (investment adviser firm), and FMR Co., Inc. (2001-2005), Senior Vice President of the Fidelity funds (2001-2005), and managed a number of Fidelity funds. Ms. Abigail P. Johnson and Mr. Arthur E. Johnson are not related.

Annual Report

* Trustee has been determined to be an "Interested Trustee" by virtue of, among other things, her affiliation with the trust or various entities under common control with FMR.

Independent Trustees:

Correspondence intended for each Independent Trustee (that is, the Trustees other than the Interested Trustee) may be sent to Fidelity Investments, P.O. Box 55235, Boston, Massachusetts 02205-5235.

Name, Year of Birth; Principal Occupations and Other Relevant Experience⁺
Elizabeth S. Acton (1951)
Year of Election or Appointment: 2013 Trustee
	Ms. Acton also serves as Trustee or Member of the Advisory Board of other Fidelity funds. Prior to her retirement in April 2012, Ms. Acton was Executive Vice President, Finance (2011-2012), Executive Vice President, Chief Financial Officer (2002-2011), and Treasurer (2004-2005) of Comerica Incorporated (financial services). Prior to joining Comerica, Ms. Acton held a variety of positions at Ford Motor Company (1983-2002), including Vice President and Treasurer (2000-2002) and Executive Vice President and Chief Financial Officer of Ford Motor Credit Company (1998-2000). Ms. Acton currently serves as a member of the Board of Directors and Audit and Finance Committees of Beazer Homes USA, Inc. (homebuilding, 2012-present).
John Engler (1948)
Year of Election or Appointment: 2014 Trustee
	Mr. Engler also serves as Trustee or Member of the Advisory Board of other Fidelity funds. He serves as president of the Business Roundtable (2011-present), and on the board of directors/trustees for Universal Forest Products (manufacturer and distributor of wood and wood-alternative products, 2003-present), K12 Inc. (technology-based education company, 2012-present), and the Annie E. Casey Foundation (2004-present). Previously, Mr. Engler served as a trustee of The Munder Funds (2003-2014), president and CEO of the National Association of Manufacturers (2004-2011) and as governor of Michigan (1991-2003). He is a past chairman of the National Governors Association.
Albert R. Gamper, Jr. (1942)
Year of Election or Appointment: 2006 Trustee Chairman of the Independent Trustees
	Mr. Gamper also serves as Trustee of other Fidelity funds. Prior to his retirement in December 2004, Mr. Gamper served as Chairman of the Board of CIT Group Inc. (commercial finance). During his tenure with CIT Group Inc. Mr. Gamper served in numerous senior management positions, including Chairman (1987-1989; 1999-2001; 2002-2004), Chief Executive Officer (1987-2004), and President (2002-2003). Mr. Gamper currently serves as a member of the Board of Directors of Public Service Enterprise Group (utilities, 2000-present), and Member of the Board of Trustees of Barnabas Health Care System (1997-present). Previously, Mr. Gamper served as Vice Chairman of the Independent Trustees of certain Fidelity funds (2011-2012) and as Chairman of the Board of Governors, Rutgers University (2004-2007).
Robert F. Gartland (1951)
Year of Election or Appointment: 2010 Trustee
	Mr. Gartland also serves as Trustee of other Fidelity funds. Mr. Gartland is Chairman and an investor in Gartland and Mellina Group Corp. (consulting, 2009-present). Previously, Mr. Gartland served as a partner and investor of Vietnam Partners LLC (investments and consulting, 2008-2011). Prior to his retirement, Mr. Gartland held a variety of positions at Morgan Stanley (financial services, 1979-2007) including Managing Director (1987-2007).
Arthur E. Johnson (1947)
Year of Election or Appointment: 2008 Trustee
	Mr. Johnson also serves as Trustee of other Fidelity funds. Mr. Johnson serves as a member of the Board of Directors of Eaton Corporation plc (diversified power management, 2009-present), AGL Resources, Inc. (holding company, 2002-present) and Booz Allen Hamilton (management consulting, 2011-present). Prior to his retirement, Mr. Johnson served as Senior Vice President of Corporate Strategic Development of Lockheed Martin Corporation (defense contractor, 1999-2009). He previously served on the Board of Directors of IKON Office Solutions, Inc. (1999-2008) and Delta Airlines (2005-2007). Mr. Arthur E. Johnson is not related to Ms. Abigail P. Johnson.
Michael E. Kenneally (1954)
Year of Election or Appointment: 2009 Trustee
	Mr. Kenneally also serves as Trustee of other Fidelity funds. Mr. Kenneally served as a Member of the Advisory Board for certain Fidelity funds before joining the Board of Trustees (2008-2009). Prior to his retirement, Mr. Kenneally served as Chairman and Global Chief Executive Officer of Credit Suisse Asset Management. Before joining Credit Suisse, he was an Executive Vice President and Chief Investment Officer for Bank of America Corporation. Earlier roles at Bank of America included Director of Research, Senior Portfolio Manager and Research Analyst, and Mr. Kenneally was awarded the Chartered Financial Analyst (CFA) designation in 1991.
James H. Keyes (1940)
Year of Election or Appointment: 2007 Trustee
	Mr. Keyes also serves as Trustee of other Fidelity funds. Mr. Keyes serves as a member of the Board and Non-Executive Chairman of Navistar International Corporation (manufacture and sale of trucks, buses, and diesel engines, since 2002). Previously, Mr. Keyes served as a member of the Board of Pitney Bowes, Inc. (integrated mail, messaging, and document management solutions, 1998-2013). Prior to his retirement, Mr. Keyes served as Chairman (1993-2002) and Chief Executive Officer (1988-2002) of Johnson Controls (automotive, building, and energy) and as a member of the Board of LSI Logic Corporation (semiconductor technologies, 1984-2008).
Marie L. Knowles (1946)
Year of Election or Appointment: 2001 Trustee Vice Chairman of the Independent Trustees
	Ms. Knowles also serves as Trustee of other Fidelity funds. Prior to Ms. Knowles' retirement in June 2000, she served as Executive Vice President and Chief Financial Officer of Atlantic Richfield Company (ARCO) (diversified energy, 1996-2000). From 1993 to 1996, she was a Senior Vice President of ARCO and President of ARCO Transportation Company. She served as a Director of ARCO from 1996 to 1998. Ms. Knowles currently serves as a Director and Chairman of the Audit Committee of McKesson Corporation (healthcare service, since 2002). Ms. Knowles is a member of the Board of the Catalina Island Conservancy and of the Santa Catalina Island Company (2009-present). She also serves as a member of the Advisory Board for the School of Engineering of the University of Southern California. Previously, Ms. Knowles served as a Director of Phelps Dodge Corporation (copper mining and manufacturing, 1994-2007), URS Corporation (engineering and construction, 2000-2003) and America West (airline, 1999-2002).

Annual Report

Advisory Board Member and Officers:

Correspondence intended for each officer and Geoffrey A. von Kuhn may be sent to Fidelity Investments, 245 Summer Street, Boston, Massachusetts 02210. Officers appear below in alphabetical order.

Name, Year of Birth; Principal Occupation
Geoffrey A. von Kuhn (1951)
Year of Election or Appointment: 2015 Member of the Advisory Board
	Mr. von Kuhn also serves as a Trustee or Member of the Advisory Board of other Fidelity funds. Mr. von Kuhn is Chief Administrative Officer for FMR LLC (diversified financial services company, 2013-present), a Director of Pembroke Real Estate, Inc. (2009-present), and a Director of Discovery Natural Resources LLC (2012-present). Previously, Mr. von Kuhn was a managing director of Crosby Group (private wealth management company, 2007-2013), a member of the management committee and senior executive in the Wealth Management Group of AmSouth Bank (2001-2006), and head of the U.S. private bank at Citigroup (2000-2001).
Elizabeth Paige Baumann (1968)
Year of Election or Appointment: 2012 Anti-Money Laundering (AML) Officer
	Ms. Baumann also serves as AML Officer of other funds. She is Chief AML Officer of FMR LLC (diversified financial services company, 2012-present) and is an employee of Fidelity Investments. Previously, Ms. Baumann served as Vice President and Deputy Anti-Money Laundering Officer (2007-2012).
Marc Bryant (1966)
Year of Election or Appointment: 2013 Assistant Secretary
	Mr. Bryant also serves as an officer of other funds. He is Senior Vice President and Deputy General Counsel of FMR LLC (diversified financial services company). Previously, Mr. Bryant served as Secretary and Chief Legal Officer of Fidelity Rutland Square Trust II (2010-2014). Prior to joining Fidelity Investments, Mr. Bryant served as a Senior Vice President and the Head of Global Retail Legal for AllianceBernstein L.P. (2006-2010), and as the General Counsel for ProFund Advisors LLC (2001-2006).
Jonathan Davis (1968)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Davis also serves as Assistant Treasurer of other funds. Mr. Davis is an employee of Fidelity Investments. Previously, Mr. Davis served as Vice President and Associate General Counsel of FMR LLC (diversified financial services company, 2003-2010).
Adrien E. Deberghes (1967)
Year of Election or Appointment: 2010 Assistant Treasurer
	Mr. Deberghes also serves as an officer of other funds. He is an employee of Fidelity Investments (2008-present). Prior to joining Fidelity Investments, Mr. Deberghes was Senior Vice President of Mutual Fund Administration at State Street Corporation (2007-2008), Senior Director of Mutual Fund Administration at Investors Bank & Trust (2005-2007), and Director of Finance for Dunkin' Brands (2000-2005).
Stephanie J. Dorsey (1969)
Year of Election or Appointment: 2013 President and Treasurer
	Ms. Dorsey also serves as an officer of other funds. She is an employee of Fidelity Investments (2008-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Dorsey served as Treasurer (2004-2008) of the JPMorgan Mutual Funds and Vice President (2004-2008) of JPMorgan Chase Bank.
Howard J. Galligan III (1966)
Year of Election or Appointment: 2014 Chief Financial Officer
	Mr. Galligan also serves as Chief Financial Officer of other funds. Mr. Galligan serves as President of Fidelity Pricing and Cash Management Services (FPCMS) (2014-present) and as a Director of Strategic Advisers, Inc. (investment adviser firm, 2008-present). Previously, Mr. Galligan served as Chief Administrative Officer of Asset Management (2011-2014) and Chief Operating Officer and Senior Vice President of Investment Support for Strategic Advisers, Inc. (2003-2011).
Scott C. Goebel (1968)
Year of Election or Appointment: 2008 Secretary and Chief Legal Officer (CLO)
	Mr. Goebel serves as Secretary and CLO of other funds. Mr. Goebel also serves as Secretary of Fidelity SelectCo, LLC (investment adviser firm, 2013-present), Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2010-present) and Fidelity Research and Analysis Company (FRAC) (investment adviser firm, 2010-present); General Counsel, Secretary, and Senior Vice President of FMR (investment adviser firm, 2008-present) and FMR Co., Inc. (investment adviser firm, 2008-present); Chief Legal Officer of Fidelity Management & Research (Hong Kong) Limited (investment adviser firm, 2008-present); and Assistant Secretary of Fidelity Management & Research (Japan) Limited (investment adviser firm, 2008-present) and FMR Investment Management (U.K.) Limited (investment adviser firm, 2008-present). Previously, Mr. Goebel served as Secretary and CLO of other Fidelity funds (2008-2013), Assistant Secretary of FIMM (2008-2010), FRAC (2008-2010), and certain funds (2007-2008); and as Vice President and Secretary of Fidelity Distributors Corporation (FDC) (2005-2007). Mr. Goebel has been employed by FMR LLC (diversified financial services company) or an affiliate since 2001.
Chris Maher (1972)
Year of Election or Appointment: 2013 Assistant Treasurer
	Mr. Maher serves as Assistant Treasurer of other funds. Mr. Maher is Vice President of Valuation Oversight and is an employee of Fidelity Investments. Previously, Mr. Maher served as Vice President of Asset Management Compliance (2013), Vice President of the Program Management Group of FMR (investment adviser firm, 2010-2013), and Vice President of Valuation Oversight (2008-2010).
Nancy D. Prior (1967)
Year of Election or Appointment: 2014 Vice President
	Ms. Prior also serves as Vice President of other funds. Ms. Prior serves as a Director of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2014-present), President, Fixed Income (2014-present), Vice Chairman of Pyramis Global Advisors, LLC (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2002-present). Previously, Ms. Prior served as Vice President of Fidelity's Money Market Funds (2012-2014), President, Money Market and Short Duration Bond of FMR (investment adviser firm, 2013-2014), President, Money Market Group of FMR (2011-2014), Managing Director of Research (2009-2011), Senior Vice President and Deputy General Counsel (2007-2009), and Assistant Secretary of other Fidelity funds (2008-2009).
Kenneth B. Robins (1969)
Year of Election or Appointment: 2009 Assistant Treasurer
	Mr. Robins also serves as an officer of other funds. Mr. Robins serves as Executive Vice President of Fidelity Investments Money Management, Inc. (FIMM) (investment adviser firm, 2013-present) and is an employee of Fidelity Investments (2004-present). Previously, Mr. Robins served in other fund officer roles.
Stephen Sadoski (1971)
Year of Election or Appointment: 2013 Deputy Treasurer
	Mr. Sadoski also serves as Deputy Treasurer of other funds. He is an employee of Fidelity Investments (2012-present) and has served in another fund officer role. Prior to joining Fidelity Investments, Mr. Sadoski served as an assistant chief accountant in the Division of Investment Management of the Securities and Exchange Commission (SEC) (2009-2012) and as a senior manager at Deloitte & Touche LLP (1997-2009).
Stacie M. Smith (1974)
Year of Election or Appointment: 2013 Assistant Treasurer
	Ms. Smith also serves as an officer of other funds. She is an employee of Fidelity Investments (2009-present) and has served in other fund officer roles. Prior to joining Fidelity Investments, Ms. Smith served as Senior Audit Manager of Ernst & Young LLP (1996-2009).
Renee Stagnone (1975)
Year of Election or Appointment: 2013 Deputy Treasurer
	Ms. Stagnone also serves as Deputy Treasurer of other funds. Ms. Stagnone is an employee of Fidelity Investments.
Michael H. Whitaker (1967)
Year of Election or Appointment: 2008 Chief Compliance Officer
	Mr. Whitaker also serves as Chief Compliance Officer of other funds. Mr. Whitaker also serves as Compliance Officer of FMR Co., Inc. (investment adviser firm, 2014-present), FMR (investment adviser firm, 2014-present), Fidelity Investments Money Management, Inc. (investment adviser firm, 2014-present), and is an employee of Fidelity Investments (2007-present). Prior to joining Fidelity Investments, Mr. Whitaker worked at MFS Investment Management where he served as Senior Vice President and Chief Compliance Officer (2004-2006), and Assistant General Counsel.
Joseph F. Zambello (1957)
Year of Election or Appointment: 2011 Deputy Treasurer
	Mr. Zambello also serves as Deputy Treasurer of other funds. Mr. Zambello is an employee of Fidelity Investments. Previously, Mr. Zambello served as Vice President of the Program Management Group of FMR (investment adviser firm, 2009-2011) and Vice President of the Transfer Agent Oversight Group (2005-2009).

Annual Report

Distributions (Unaudited)

A total of 50.76% of the dividends distributed during the fiscal year was derived from interest on U.S. Government securities which is generally exempt from state income tax.

The fund designates $530,010 of distributions paid during the period January 1, 2015 to April 30, 2015 as qualifying to be taxed as interest-related dividends for nonresident alien shareholders.

The fund will notify shareholders in January 2016 of amounts for use in preparing 2015 income tax returns.

Annual Report

Board Approval of Investment Advisory Contracts and Management Fees

Fidelity Government Money Market Fund

Based on its review, the Board concluded that the nature, extent, and quality of the services provided to the fund should benefit the fund's shareholders.

Annual Report

Based on its review, the Board concluded that the fund's management fee and total expenses were reasonable in light of the services that the fund receives and the other factors considered.

Annual Report

Investment Adviser

Fidelity Management & Research Company
Boston, MA

Investment Sub-Advisers

Fidelity Investments
Money Management, Inc.

FMR Investment Management
U.K. Limited

Fidelity Management & Research
(Hong Kong) Limited

Fidelity Management & Research
(Japan) Limited

General Distributor

Fidelity Distributors Corporation

Smithfield, RI

Transfer and Service Agents

Fidelity Investments Institutional
Operations Company, Inc.

Boston, MA

Fidelity Service Company, Inc.

Boston, MA

Custodian

JPMorgan Chase Bank

New York, NY

The Fidelity Telephone Connection

Mutual Fund 24-Hour Service

Exchanges/Redemptions
and Account Assistance 1-800-544-6666

Product Information 1-800-544-6666

Retirement Accounts 1-800-544-4774 (8 a.m. - 9 p.m.)

TDD Service 1-800-544-0118
for the deaf and hearing impaired
(9 a.m. - 9 p.m. Eastern time)

Fidelity Automated Service
Telephone (FAST®) for314
1-800-544-5555

Automated line for quickest service

(Fidelity Investment logo)(registered trademark)
Corporate Headquarters
245 Summer St., Boston, MA 02210
www.fidelity.com

SPU-ANN-0615
1.703529.117

Item 2. Code of Ethics

As of the end of the period, April 30, 2015, Fidelity Hereford Street Trust (the trust) has adopted a code of ethics, as defined in Item 2 of Form N-CSR, that applies to its President and Treasurer and its Chief Financial Officer. A copy of the code of ethics is filed as an exhibit to this Form N-CSR.

Item 3. Audit Committee Financial Expert

The Board of Trustees of the trust has determined that James H. Keyes is an audit committee financial expert, as defined in Item 3 of Form N-CSR. Mr. Keyes is independent for purposes of Item 3 of Form N-CSR.

Item 4. Principal Accountant Fees and Services

Fees and Services

The following table presents fees billed by Deloitte & Touche LLP, the member firms of Deloitte Touche Tohmatsu, and their respective affiliates (collectively, "Deloitte Entities") in each of the last two fiscal years for services rendered to Fidelity Treasury Money Market Fund (the "Fund"):

Services Billed by Deloitte Entities

April 30, 2015 Fees^A

	Audit Fees	Audit-Related Fees	Tax Fees	All Other Fees
Fidelity Treasury Money Market Fund	$28,000	$-	$5,000	$700

April 30, 2014 Fees^A,B

	Audit Fees	Audit-Related Fees	Tax Fees	All Other Fees
Fidelity Treasury Money Market Fund	$23,000	$-	$4,700	$400

^AAmounts may reflect rounding.

^BFidelity Treasury Money Market Fund commenced operations on July 2, 2013.

The following table presents fees billed by PricewaterhouseCoopers LLP ("PwC") in each of the last two fiscal years for services rendered to Fidelity Government Money Market Fund, Fidelity Money Market Fund and Fidelity Treasury Only Money Market Fund (the "Funds"):

Services Billed by PwC

April 30, 2015 Fees^A

	Audit Fees	Audit-Related Fees	Tax Fees	All Other Fees
Fidelity Government Money Market Fund	$51,000	$-	$2,200	$7,000
Fidelity Money Market Fund	$40,000	$-	$2,200	$2,400
Fidelity Treasury Only Money Market Fund	$42,000	$-	$2,200	$3,300

April 30, 2014 Fees^A

	Audit Fees	Audit-Related Fees	Tax Fees	All Other Fees
Fidelity Government Money Market Fund	$52,000	$-	$2,100	$6,500
Fidelity Money Market Fund	$41,000	$-	$2,100	$2,500
Fidelity Treasury Only Money Market Fund	$44,000	$-	$2,100	$3,500

^AAmounts may reflect rounding.

The following table presents fees billed by PwC and Deloitte Entities that were required to be approved by the Audit Committee for services that relate directly to the operations and financial reporting of the Funds and that are rendered on behalf of Fidelity Management & Research Company ("FMR") and entities controlling, controlled by, or under common control with FMR (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser) that provide ongoing services to the Funds ("Fund Service Providers"):

Services Billed by Deloitte Entities

	April 30, 2015^A,	April 30, 2014^A,B
Audit-Related Fees	$-	$765,000
Tax Fees	$-	$-
All Other Fees	$220,000	$695,000

^A Amounts may reflect rounding.

^B May include amounts billed prior to the Treasury Money Market Fund's commencement of operations.

Services Billed by PwC

	April 30, 2015^A	April 30, 2014^A
Audit-Related Fees	$5,900,000	$4,970,000
Tax Fees	$-	$-
All Other Fees	$-	$50,000

^A Amounts may reflect rounding.

"Audit-Related Fees" represent fees billed for assurance and related services that are reasonably related to the performance of the fund audit or the review of the fund's financial statements and that are not reported under Audit Fees.

"Tax Fees" represent fees billed for tax compliance, tax advice or tax planning that relate directly to the operations and financial reporting of the fund.

"All Other Fees" represent fees billed for services provided to the fund or Fund Service Provider, a significant portion of which are assurance related, that relate directly to the operations and financial reporting of the fund, excluding those services that are reported under Audit Fees, Audit-Related Fees or Tax Fees.

Assurance services must be performed by an independent public accountant.

* * *

The aggregate non-audit fees billed by PwC and Deloitte Entities for services rendered to the Funds, FMR (not including any sub-adviser whose role is primarily portfolio management and is subcontracted with or overseen by another investment adviser), and any Fund Service Provider for each of the last two fiscal years of the Funds are as follows:

Billed By	April 30, 2015^A	April 30, 2014^A,B
Deloitte Entities	$1,300,000	$1,580,000
PwC	$8,085,000	$5,555,000

^A Amounts may reflect rounding.

^B May include amounts billed prior to the Treasury Money Market Fund's commencements of operations.

The trust's Audit Committee has considered non-audit services that were not pre-approved that were provided by PwC and Deloitte Entities to Fund Service Providers to be compatible with maintaining the independence of PwC and Deloitte Entities in their audits of the Funds, taking into account representations from PwC and Deloitte Entities, in accordance with Public Company Accounting Oversight Board rules, regarding their independence from the Funds and their related entities and FMR's review of the appropriateness and permissibility under applicable law of such non-audit services prior to their provision to the Fund Service Providers.

Audit Committee Pre-Approval Policies and Procedures

The trust's Audit Committee must pre-approve all audit and non-audit services provided by a fund's independent registered public accounting firm relating to the operations or financial reporting of the fund. Prior to the commencement of any audit or non-audit services to a fund, the Audit Committee reviews the services to determine whether they are appropriate and permissible under applicable law.

The Audit Committee has adopted policies and procedures to, among other purposes, provide a framework for the Committee's consideration of non-audit services by the audit firms that audit the Fidelity funds. The policies and procedures require that any non-audit service provided by a fund audit firm to a Fidelity fund and any non-audit service provided by a fund auditor to a Fund Service Provider that relates directly to the operations and financial reporting of a Fidelity fund ("Covered Service") are subject to approval by the Audit Committee before such service is provided.

All Covered Services must be approved in advance of provision of the service either: (i) by formal resolution of the Audit Committee, or (ii) by oral or written approval of the service by the Chair of the Audit Committee (or if the Chair is unavailable, such other member of the Audit Committee as may be designated by the Chair to act in the Chair's absence). The approval contemplated by (ii) above is permitted where the Treasurer determines that action on such an engagement is necessary before the next meeting of the Audit Committee.

Non-audit services provided by a fund audit firm to a Fund Service Provider that do not relate directly to the operations and financial reporting of a Fidelity fund are reported to the Audit Committee on a periodic basis.

Non-Audit Services Approved Pursuant to Rule 2-01(c)(7)(i)(C) and (ii) of Regulation S-X ("De Minimis Exception")

There were no non-audit services approved or required to be approved by the Audit Committee pursuant to the De Minimis Exception during the Funds' last two fiscal years relating to services provided to (i) the Funds or (ii) any Fund Service Provider that relate directly to the operations and financial reporting of the Funds.

Item 5. Audit Committee of Listed Registrants

Not applicable.

Item 6. Investments

(a) Not applicable.

(b) Not applicable

Item 7. Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies

Not applicable.

Item 8. Portfolio Managers of Closed-End Management Investment Companies

Not applicable.

Item 9. Purchase of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers

Not applicable.

Item 10. 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 trust's Board of Trustees.

Item 11. Controls and Procedures

(a)(i) The President and Treasurer and the Chief Financial Officer have concluded that the trust's 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 second fiscal quarter of 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 12. Exhibits

(a)	(1)	Code of Ethics pursuant to Item 2 of Form N-CSR is filed and attached hereto as EX-99.CODE ETH.
(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 Hereford Street Trust

By:	/s/Stephanie J. Dorsey
	Stephanie J. Dorsey
	President and Treasurer

Date:	June 26, 2015

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/Stephanie J. Dorsey
	Stephanie J. Dorsey
	President and Treasurer

Date:	June 26, 2015

By:	/s/Howard J. Galligan III
	Howard J. Galligan III
	Chief Financial Officer

Date:	June 26, 2015

Fidelity Hereford Street Trust N-CSRCertified annual shareholder report (management investment company)

Contents

Shareholder Expense Example

Investment Changes/Performance (Unaudited)

Investments April 30, 2015

Statement of Assets and Liabilities

Statement of Operations

Statement of Changes in Net Assets

Financial Highlights

Contents

Shareholder Expense Example

Investment Changes/Performance (Unaudited)

Investments April 30, 2015

Statement of Assets and Liabilities

Statement of Operations

Statement of Changes in Net Assets

Financial Highlights

Contents

Shareholder Expense Example

Investment Changes/Performance (Unaudited)

Investments April 30, 2015

Statement of Assets and Liabilities

Statement of Assets and Liabilities - continued

Statement of Operations

Statement of Changes in Net Assets

Financial Highlights - Fidelity Money Market Fund

Financial Highlights - Premium Class

Contents

Shareholder Expense Example

Investment Changes/Performance (Unaudited)

Investments April 30, 2015

Statement of Assets and Liabilities

Statement of Assets and Liabilities - continued

Statement of Operations

Statement of Changes in Net Assets

Financial Highlights - Capital Reserves Class

Financial Highlights - Daily Money Class

Financial Highlights - Fidelity Government Money Market Fund

Financial Highlights - Premium Class