UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 1, 2026 (May 27, 2026)

PRINCIPAL FINANCIAL GROUP, INC.

(Exact name of registrant as specified in its charter)

711 High Street, Des Moines, Iowa 50392

(Address of principal executive offices)

(515) 247-5111

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company    ¨

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Securities registered pursuant to Section 12(b) of the Act:

Item 1.01 Entry Into a Material Definitive Agreement.

On June 1, 2026, Principal Financial Group, Inc. (the “Company”) issued $400,000,000 aggregate principal amount of its 5.300% Senior Notes due 2037 (the “Notes”). The Notes were issued pursuant to the Senior Indenture, dated as of May 21, 2009 (the “Senior Indenture”), among the Company, as issuer, Principal Financial Services, Inc. (“PFSI”), as guarantor, and The Bank of New York Mellon Trust Company, N.A., as trustee, as supplemented by the Eighteenth Supplemental Indenture, dated as of June 1, 2026 (the “Supplemental Indenture”). The Notes are fully and unconditionally guaranteed by PFSI pursuant to the guarantee, dated as of June 1, 2026 (the “Guarantee”).

The Notes were sold pursuant to an effective automatic shelf registration statement on Form S-3 (the “Registration Statement”) (File Nos. 333-293726 and 333-293726-01) which became effective upon filing with the Securities and Exchange Commission on February 25, 2026. The closing of the sale of the Notes occurred on June 1, 2026. The Senior Indenture, the Supplemental Indenture (including the form of the Note) and the Guarantee of PFSI are filed as Exhibits 4.1, 4.2 and 4.3 hereto, respectively, and are incorporated by reference herein.

Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

The information contained in Item 1.01 of this Current Report on Form 8-K is incorporated herein by reference.

Item 8.01 Other Events.

Underwriting Agreement.

In connection with the issuance and sale of the Notes, the Company entered into the Underwriting Agreement, dated May 27, 2026 (the “Underwriting Agreement”), among the Company, PFSI and BofA Securities, Inc., Goldman Sachs & Co. LLC and J.P. Morgan Securities LLC, as representatives of the underwriters named in Schedule I thereto, relating to the Notes. The Underwriting Agreement is filed as Exhibit 1.1 hereto, and is incorporated by reference herein.

Opinions of Counsel.

The opinion of Debevoise & Plimpton LLP, relating to the validity of the Notes and the related Guarantee, is filed as Exhibit 5.1 hereto. The opinion of George Djurasovic, Vice President and Interim General Counsel of the Company and PFSI, relating to certain legal matters relating to the issuance of the Guarantee, is filed as Exhibit 5.2 hereto.

Item 9.01 Financial Statements and Exhibits.

The exhibits to this Current Report on Form 8-K (except Exhibit 104) are hereby incorporated by reference into the Registration Statement.

(d) Exhibits.

SIGNATURES

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