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: 811-08279

T. Rowe Price Reserve Investment Funds, Inc.

(Exact name of registrant as specified in charter)

1307 Point Street, Baltimore, MD 21231

(Address of principal executive offices)

David Oestreicher

1307 Point Street, Baltimore, MD 21231

(Name and address of agent for service)

Registrant’s telephone number, including area code: (410) 345-2000

Date of fiscal year end: May 31

Date of reporting period: May 31, 2026

Item 1. Reports to Shareholders

(a) Report pursuant to Rule 30e-1

Item 1.  (b) Notice pursuant to Rule 30e-3.

Not applicable.

Item 2.  Code of Ethics.

The registrant has adopted a code of ethics, as defined in Item 2 of Form N-CSR, applicable to its principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions. A copy of this code of ethics is filed as an exhibit to this Form N-CSR. No substantive amendments were approved or waivers were granted to this code of ethics during the period covered by this report.

Item 3.  Audit Committee Financial Expert.

The registrant’s Board of Directors has determined that Mr. Paul F. McBride qualifies as an audit committee financial expert, as defined in Item 3 of Form N-CSR. Mr. McBride is considered independent for purposes of Item 3 of Form N-CSR.

Item 4.  Principal Accountant Fees and Services.

(a) – (d) Aggregate fees billed for the last two fiscal years for professional services rendered to, or on behalf of, the registrant by the registrant’s principal accountant were as follows:

Audit fees include amounts related to the audit of the registrant’s annual financial statements and services normally provided by the accountant in connection with statutory and regulatory filings. Audit-related fees include amounts reasonably related to the performance of the audit of the registrant’s financial statements and specifically include the issuance of a report on internal controls and, if applicable, agreed-upon procedures related to fund acquisitions. Tax fees include amounts related to services for tax compliance, tax planning, and tax advice. The nature of these services specifically includes the review of distribution calculations and the preparation of Federal, state, and excise tax returns. All other fees include the registrant’s pro-rata share of amounts for agreed-upon procedures in conjunction with service contract approvals by the registrant’s Board of Directors/Trustees.

(e)(1)  The registrant’s audit committee has adopted a policy whereby audit and non-audit services performed by the registrant’s principal accountant for the registrant, its investment adviser, and any entity controlling, controlled by, or under common control with the investment adviser that provides ongoing services to the registrant require pre-approval in advance at regularly scheduled audit committee meetings. If such a service is required between regularly scheduled audit committee meetings, pre-approval may be authorized by one audit committee member with ratification at the next scheduled audit committee meeting. Waiver of pre-approval for audit or non-audit services requiring fees of a de minimis amount is not permitted.

(2)  No services included in (b) – (d) above were approved pursuant to paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X.

(f)  Less than 50 percent of the hours expended on the principal accountant’s engagement to audit the registrant’s financial statements for the most recent fiscal year were attributed to work performed by persons other than the principal accountant’s full-time, permanent employees.

(g)  The aggregate fees billed for the most recent fiscal year and the preceding fiscal year by the registrant’s principal accountant for non-audit services rendered to the registrant, its investment adviser, and any entity controlling, controlled by, or under common control with the investment adviser that provides ongoing services to the registrant were $1,211,000 and $1,746,000, respectively.

(h)  All non-audit services rendered in (g) above were pre-approved by the registrant’s audit committee. Accordingly, these services were considered by the registrant’s audit committee in maintaining the principal accountant’s independence.

(i)  Not applicable.

(j)  Not applicable.

Item 5.  Audit Committee of Listed Registrants.

Not applicable.

Item 6.  Investments.

(a)  Not applicable. The complete schedule of investments is included in Item 7 of this Form N-CSR.

(b)  Not applicable.

Item 7.  Financial Statements and Financial Highlights for Open-End Management Investment Companies.

(a – b)  Report pursuant to Regulation S-X.

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

Not applicable.

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

Not applicable.

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

Remuneration paid to Directors is included in Item 7 of this Form N-CSR.

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

If applicable, see Item 7.

Item 12.  Disclosure of Proxy Voting Policies and Procedures for Closed-End Management Investment Companies.

Not applicable.

Item 13.  Portfolio Managers of Closed-End Management Investment Companies.

Not applicable.

Item 14.  Purchases of Equity Securities by Closed-End Management Investment Company and Affiliated Purchasers.

Not applicable.

Item 15.  Submission of Matters to a Vote of Security Holders.

There has been no change to the procedures by which shareholders may recommend nominees to the registrant’s board of directors.

Item 16.  Controls and Procedures.

(a)  The registrant’s principal executive officer and principal financial officer have evaluated the registrant’s disclosure controls and procedures within 90 days of this filing and have concluded that the registrant’s disclosure controls and procedures were effective, as of that date, in ensuring that information required to be disclosed by the registrant in this Form N-CSR was recorded, processed, summarized, and reported timely.

(b)  The registrant’s principal executive officer and principal financial officer are aware of no change in the registrant’s internal control over financial reporting that occurred during the period covered by this report that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting.

Item 17.  Disclosure of Securities Lending Activities for Closed-End Management Investment Companies.

Not applicable.

Item 18.  Recovery of Erroneously Awarded Compensation.

Not applicable.

Item 19.  Exhibits.

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.

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.