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): April 8, 2026

METALS ACQUISITION CORP. II

(Exact name of registrant as specified in its charter)

c/o Maples Corporate Services Limited

PO Box 309

Ugland House

Grand Cayman, KY1-1104

Cayman Islands

(Address of principal executive offices, including zip code)

Registrant’s telephone number, including area code: +1 345 814 5303

Not Applicable
(Former name or former address, if changed since last report)

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

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. ☐

Item 8.01. Other Events.

On April 8, 2026, Metals Acquisition Corp. II (the “Company”) issued a press release, a copy of which is attached as Exhibit 99.1 to this Current Report on Form 8-K, announcing that the holders of the Company’s units (the “Units”) may elect to separately trade the Class A ordinary shares, par value $0.0001 per share (the “Class A Ordinary Shares”), and warrants (the “Warrants”) included in the Units commencing on or about April 14, 2026. Each Unit consists of one Class A Ordinary Share and one-third of one redeemable Warrant to purchase one Class A Ordinary Share. Any Units not separated will continue to trade on the New York Stock Exchange under the symbol “MTAL U”, and the Class A Ordinary Shares and Warrants will separately trade on the New York Stock Exchange under the symbols “MTAL” and “MTAL WS,” respectively. No fractional Warrants will be issued upon separation of the Units and only whole Warrants will trade. Holders of Units will need to have their brokers contact Continental Stock Transfer & Trust Company, the Company’s transfer agent, in order to separate the Units into Class A Ordinary Shares and Warrants.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

EXHIBIT INDEX

SIGNATURE

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.

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