UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE TO

TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1)

OF THE SECURITIES EXCHANGE ACT OF 1934

FINAL AMENDMENT

DATA STORAGE CORPORATION

(Names of Filing Persons (Issuer and Offeror))

COMMON STOCK, PAR VALUE $0.001 PER SHARE

(Title of Class of Securities)

23786R201

(CUSIP Number of Class of Securities)

Charles M. Piluso

Chief Executive Officer

Data Storage Corporation

244 5^th Avenue, Second Floor, Suite 2821

New York, New York 10001

Telephone: (212) 564-4922

(Name, Address, and Telephone Numbers of Person Authorized to Receive Notices and Communications on Behalf of Filing Persons)

With copies to:

Leslie Marlow, Esq.

Kathleen A. Cunningham, Esq.

Blank Rome LLP

1271 Avenue of the Americas

New York, NY 10020

(212) 885-5000

☐ Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

☐ third-party tender offer subject to Rule 14d-1.

☒ issuer tender offer subject to Rule 13e-4.

☐ going-private transaction subject to Rule 13e-3.

☐ amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: ☒

If applicable, check the appropriate box(es) below to designate the appropriate rule provision(s) relied upon:

☐ Rule 13e-4(i) (Cross-Border Issuer Tender Offer)

☐ Rule 14d-1(d) (Cross-Border Third-Party Tender Offer)

FINAL AMENDMENT

TO

SCHEDULE TO

This Final Amendment (“Final Amendment”) relates to and amends and supplements the Tender Offer Statement on Schedule TO (as amended, together with all exhibits including Exhibit (a)(1)(A)) (the “Schedule TO”) originally filed by Data Storage Corporation (the “Company”) with the Securities and Exchange Commission (the “SEC”) on December 8, 2025, as amended by Amendment No. 1 filed with the SEC on December 18, 2025 and Amendment No. 2 filed with the SEC on December 23, 2025 relating to the offer by the Company to purchase up to 6,192,990 shares of its common stock, par value $0.001 per share (the “Shares”), at a price of $5.20 per Share (the “Purchase Price”), in cash, less any applicable withholding taxes and without interest. The Company’s offer was made upon the terms and subject to the conditions set forth in the Offer to Purchase, dated December 8, 2025 and the related Letter of Transmittal, copies of which were previously filed as exhibits to the Schedule TO (which together, as amended or supplemented from time to time, constitute the “Offer”).

This Final Amendment is being filed to amend and supplement the Schedule TO. Except as amended hereby to the extent specifically provided herein, all terms of the Offer and all other disclosures set forth in the Schedule TO and the exhibits thereto remain unchanged and are hereby expressly incorporated into this Amendment by reference. Capitalized terms used and not otherwise defined in this Final Amendment shall have the meanings assigned to such terms in the Schedule TO.

This Final Amendment is being filed to report the results of the Offer and is intended to satisfy the reporting requirements of Rule 13e-4(c)(4) promulgated under the Securities Exchange Act of 1934, as amended. All information in the Offer and the Schedule TO is expressly incorporated by reference herein.

The following information is provided pursuant to Rule 13e-4(c)(4):

Item 8. Interest of Securities of the Subject Company

Item 8(b) of the Schedule TO is hereby amended and supplemented by adding the following text:

On December 11, 2025, Todd Correll exercised options to purchase 20,627 shares of common stock, of which 10,471 shares were sold in the open market to satisfy tax withholding obligations and 10,156 shares were withheld from issuance to cover the exercise price of the options exercised.

On December 12, 2025, Matthew Grover exercised options to purchase 20,627 shares of common stock, of which 10, 202 shares were withheld from issuance to cover the exercise price of the options exercised.

On December 10, 2025, Thomas Kempster sold 6,846 shares in open market sales to satisfy tax withholding obligations.

On December 11, 2025, Lawrence Maglione exercised options to purchase 24,167 shares of common stock of which 21,529 shares were sold in open market sales to satisfy tax withholding obligations and 11,631 shares were withheld from issuance to cover the exercise price of options exercised.

On December 10, 2025, Charles Piluso sold 20,089 shares in open market sales to satisfy tax withholding obligations.

On December 16, 2025, Harold Schwartz exercised options to purchase 36,823 shares of common stock.

On January 14, 2026 the Company’s directors and officers tendered the following number of Shares beneficially owned in connection with the Offer:

ITEM 11. ADDITIONAL INFORMATION

Item 11 is hereby amended and supplemented as follows:

On January 15, 2026, the Company issued a press release announcing the final results of the tender offer. A copy of such press release is filed as Exhibit (a)(8) to this Schedule TO and is incorporated herein by reference.

ITEM 12 EXHIBITS

Item 12 of the Schedule TO is hereby amended and restated as follows:

Exhibit

* filed herewith

**previously filed

SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.