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): August 18, 2025

TERAWULF INC.

(Exact name of registrant as specified in its charter)

9 Federal Street

Easton, Maryland 21601

(Address of principal executive offices) (Zip Code)

(410) 770-9500

(Registrant’s telephone number, including area code)

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 (see General Instruction A.2. below):

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

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. ¨

Item 8.01. Other Events.

Convertible Notes Offering

On August 18, 2025, TeraWulf Inc. (the “Company”) issued a press release announcing the upsize and pricing of its private offering of $850 million aggregate principal amount of its 1.00% Convertible Senior Notes due 2031 (the “Offering”). The notes will only be sold to persons reasonably believed to be qualified institutional buyers pursuant to Rule 144A under the Securities Act of 1933, as amended. The Company also granted to the initial purchasers of the notes an option to purchase, within a 13-day period beginning on, and including, the date on which the notes are first issued, up to an additional $150 million aggregate principal amount of the notes. The offering is expected to close on August 20, 2025, subject to satisfaction of customary closing conditions.

The Company estimates that the net proceeds of the offering will be approximately $828.7 million (or approximately $975.2 million if the initial purchasers exercise in full their option to purchase additional notes), after deducting the initial purchasers’ discounts and commissions and estimated offering expenses payable by the Company. The Company intends to use approximately $85.5 million of the net proceeds from the sale of the notes to pay the cost of certain capped call transactions with the remaining net proceeds used to fund a portion of the Company’s data center expansion and for general corporate purposes.

A copy of the press release announcing the pricing of the offering is filed as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

The information included in this Current Report on Form 8-K is neither an offer to sell nor a solicitation of an offer to buy any securities.

Cautionary Note Regarding Forward-Looking Statements

Statements in this Current Report on Form 8-K about future expectations, plans, and prospects, as well as any other statements regarding matters that are not historical facts, may constitute “forward-looking statements” within the meaning of The Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to, statements relating to the completion, size and timing of the offering, the anticipated use of any proceeds from the offering, and the terms of the notes. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including uncertainties related to market conditions and the completion of the offering on the anticipated terms or at all, the other factors discussed in the “Risk Factors” section of TeraWulf’s Annual Report on Form 10-K filed with the U.S. Securities and Exchange Commission (the “SEC”) on March 3, 2025, the “Risk Factors” section of TeraWulf’s Quarterly Reports on Form 10-Q and the risks described in other filings that TeraWulf may make from time to time with the SEC. Any forward-looking statements contained in this Current Report on Form 8-K speak only as of the date hereof, and TeraWulf specifically disclaims any obligation to update any forward-looking statement, whether as a result of new information, future events, or otherwise, except to the extent required by applicable law.

Item 9.01. Financial Statements and Exhibits.

(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.