Introductory Note

Unless otherwise indicated or unless the context requires otherwise, all references in this report to “we,” “us,” “our,” “our company,” “the company” or “Digital Realty” refer to Digital Realty Trust, Inc., together with its consolidated subsidiaries, including Digital Realty Trust, L.P., our “operating partnership.”

Item 1.01. Entry into a Material Definitive Agreement.

On October 6, 2026, Digital Constellation B.V., an indirect wholly owned finance subsidiary of the operating partnership, issued and sold CHF225 million aggregate principal amount of 1.6803% Guaranteed Notes due 2029 (the “2029 Notes”), CHF185 million aggregate principal amount of 2.0600% Guaranteed Notes due 2032 (the “2032 Notes”) and CHF100 million aggregate principal amount of 2.4150% Guaranteed Notes due 2036 (the “2036 Notes” and together with the 2029 Notes and the 2032 Notes, the “Swiss Franc Notes”). The Swiss Franc Notes are senior unsecured obligations of Digital Constellation B.V. and are fully and unconditionally guaranteed by Digital Realty Trust, Inc., the operating partnership and Digital Intrepid Holding B.V., an indirect wholly owned holding and finance subsidiary of the operating partnership through which the Interxion business is held. The Swiss Franc Notes were sold outside the United States in reliance on Regulation S under the Securities Act of 1933, as amended (the “Securities Act”) and in Switzerland pursuant to a public offering made in reliance on an exemption from the obligation to publish a prospectus approved by a Swiss review body pursuant to article 51(2) of the Swiss Financial Services Act and article 60 of the Swiss Financial Services Ordinance. The Swiss Franc Notes have not been and will not be registered under the Securities Act and may not be offered or sold within the United States or to United States persons (within the meaning of Regulation S under the Securities Act) absent registration or an applicable exemption from the registration requirements.

The terms of the Swiss Franc Notes are governed by terms and conditions, dated as of October 2, 2026 (the “Conditions”), a copy of which is attached hereto as Exhibit 4.1 and incorporated herein by reference. Each of the Swiss Franc Notes are evidenced by permanent global certificates, copies of which are attached hereto as Exhibit 4.2, Exhibit 4.3 and Exhibit 4.4, respectively, and incorporated herein by reference. The Conditions contain various restrictive covenants, including limitations on our ability to incur additional indebtedness and requirements to maintain a pool of unencumbered assets. The descriptions of the Conditions, the Swiss Franc Notes and the guarantees in this report are summaries and are qualified in their entirety by the terms of the Conditions and the forms of the Swiss Franc Notes.

Net proceeds from the offering of the Swiss Franc Notes were CHF508.39 million after deducting the managers’ commissions and certain offering expenses. We intend to use the net proceeds from the offering of the Swiss Franc Notes to temporarily repay borrowings outstanding under the operating partnership’s global revolving credit facilities, acquire additional properties or businesses, fund development opportunities, invest in interest-bearing accounts and short-term, interest-bearing securities which are consistent with Digital Realty Trust, Inc.’s intention to qualify as a REIT for U.S. federal income tax purposes, and to provide for working capital and other general corporate purposes, including potentially for the repayment of other debt, or the redemption, repurchase, repayment or retirement of outstanding equity or debt securities, or a combination of the foregoing.

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

On October 6, 2026, Digital Constellation B.V., an indirect wholly owned finance subsidiary of the operating partnership, issued and sold CHF225 million aggregate principal amount of 1.6803% Guaranteed Notes due 2029, CHF185 million aggregate principal amount of 2.0600 % Guaranteed Notes due 2032 and CHF100 million aggregate principal amount of 2.4150% Guaranteed Notes due 2036. The purchase price paid by the initial purchasers for the Swiss Franc Notes was 100% of the principal amount thereof. Interest on the 2029 Notes will be payable annually in arrears at a rate of 1.6803% per annum, and the 2029 Notes will mature on October 8, 2029. Interest on the 2032 Notes will be payable annually in arrears at a rate of 2.0600% per annum, and the 2032 Notes will mature on October 6, 2032. Interest on the 2029 Notes is payable on October 8 of each year beginning on October 8, 2027, interest on the 2032 Notes and 2036 Notes is payable on October 6 of each year beginning on October 6, 2027. Interest on the 2036 Notes will be payable annually in arrears at a rate of 2.4150% per annum, and

the 2036 Notes will mature on October 6, 2036. The Swiss Franc Notes are senior unsecured obligations of Digital Constellation B.V. and rank equally in right of payment with all of Digital Constellation B.V.’s other existing and future senior unsecured and unsubordinated indebtedness. Digital Constellation B.V.’s obligations under the Swiss Franc Notes are fully and unconditionally guaranteed by Digital Realty Trust, Inc., the operating partnership and Digital Intrepid Holding B.V., an indirect wholly owned holding and finance subsidiary of the operating partnership through which the Interxion business is held.

The Swiss Franc Notes are generally not redeemable at the option of Digital Constellation B.V., except as set out below.

Digital Constellation B.V. may redeem any series of Swiss Franc Notes, in whole, but not in part, on or after the date that is three months prior to the maturity date thereof, or July 8, 2029 for the 2029 Notes, July 6, 2032 for the 2032 Notes and July 6, 2036 for the 2036 Notes, at a price equal to 100% of the principal amount of such series of Swiss Franc Notes plus accrued and unpaid interest, if any, to, but excluding, the redemption date.

Additionally, at any time following the issue date and prior to the maturity date, Digital Constellation B.V. may also redeem any series of Swiss Franc Notes in whole, but not in part, at a price equal to 100% of the principal amount of such series of Swiss Franc Notes plus accrued and unpaid interest, if any, to, but excluding, the redemption date if 75% or more of the aggregate principal amount of such series of Swiss Franc Notes have been redeemed or purchased and cancelled at the time of such notice.

All payments of principal and interest on the Swiss Franc Notes will be made free and clear of and without withholding or deduction for or on account of any present or future tax, assessment or other governmental charge imposed by the United States or the Netherlands or a political subdivision or taxing authority thereof or therein having power to tax, unless the withholding of such tax, assessment or governmental charge is required by law or the official interpretation or administration thereof. In the event such withholding or deduction of taxes is required by law, then, subject to certain exceptions, Digital Constellation B.V. will pay such “additional amounts” necessary so that the net payment of the principal of and interest on the Swiss Franc Notes to a holder who is not a United States person for United States federal income tax purposes, including additional amounts, after the withholding or deduction, will not be less than the amount provided in such Swiss Franc Notes to be then due and payable.

If, due to certain changes in tax law, Digital Constellation B.V. has or will become obligated to pay additional amounts on the Swiss Franc Notes or if there is a substantial probability that Digital Constellation B.V. will become obligated to pay additional amounts on the Swiss Franc Notes, then Digital Constellation B.V. may, on giving not less than 15 days’ nor more than 45 days’ notice, at its option, redeem the Swiss Franc Notes, in whole but not in part, at a redemption price equal to 100% of the principal amount of the Swiss Franc Notes to be redeemed, together with interest accrued and unpaid, if any, to, but excluding, the redemption date.

Certain events are considered events of default, which may result in the accelerated maturity of the Swiss Franc Notes, including:

Item 7.01. Regulation FD Disclosure.

On October 6, 2026, Digital Realty issued a press release announcing the closing of the Swiss Franc Notes described under Item 1.01 above. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

The information included in this Current Report on Form 8-K under this Item 7.01 (including Exhibit 99.1) shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing made by the company or the operating partnership under the Exchange Act or the Securities Act, except as shall be expressly set forth by specific reference in such a filing.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrants have duly caused this report to be signed on their behalf by the undersigned hereunto duly authorized.

Date: October 6, 2026