6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington,D.C. 20549

FORM6-K

REPORTOF FOREIGN PRIVATE ISSUERPURSUANT TO RULE 13a-16 OR 15d-16UNDER THE SECURITIES EXCHANGE ACT OF 1934

Dated October 30, 2023

Commission File Number: 001-35788

ARCELORMITTAL

(Translation of registrant’s name into English)

24-26, Boulevard d’Avranches

L-1160 Luxembourg

Grand Duchy of Luxembourg

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒                Form 40-F ☐

On October 28, 2023, ArcelorMittal published the press release attached hereto as Exhibit 99.1 and hereby incorporated by reference into this report on Form 6-K.

ExhibitIndex

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, thereunto duly authorized.

ARCELORMITTAL

Date 30 October 2023

ARCELORMITTAL 6-K

Exhibit99.1

press release

Statementregarding tragic accident in Kazakhstan

28October 2023, 10:20 CET

ArcelorMittal can confirm that earlier on the 28^th^ October, a tragic accident occurred at its Kostenco coal mine. As at this time, 25 of our employees are confirmed dead with a further 21 still missing.  206 people were safely evacuated to the surface. No words can adequately convey the devastation the company feels following this accident.  Everything that can be done to support the families who have lost loved ones through this deeply painful time will be done.

ArcelorMittal can also confirm, as communicated earlier today by the government of Kazakhstan, that the two parties have been in discussions concerning the future of ArcelorMittal Temirtau and recently signed a preliminary agreement for a transaction that will transfer ownership to the Republic of Kazakhstan.

ArcelorMittal is committed to completing this transaction as soon as possible in order to minimise disruption to the greatest extent possible.  Both parties are very much focused on an outcome that is in the best interests of the people who work at the steel plant and iron-ore and coal mines, as well as the communities the operations support.  Further statements will be made as appropriate.

ENDS

AboutArcelorMittal

ArcelorMittalis the world's leading steel company, with a presence in 60 countries and primary steelmaking facilities in 16 countries. In 2022, ArcelorMittalhad revenues of $79.8 billion and crude steel production of 59 million metric tonnes, while iron ore production reached 50.9 millionmetric tonnes.

Ourpurpose is to produce ever smarter steels that have a positive benefit for people and planet. Steels made using innovative processeswhich use less energy, emit significantly less carbon and reduce costs. Steels that are cleaner, stronger and reusable. Steels for electricvehicles and renewable energy infrastructure that will support societies as they transform through this century. With steel at our core,our inventive people and an entrepreneurial culture at heart, we will support the world in making that change. This is what we believeit takes to be the steel company of the future.

ArcelorMittalis listed on the stock exchanges of New York (MT), Amsterdam (MT), Paris (MT), Luxembourg (MT) and on the Spanish stock exchanges ofBarcelona, Bilbao, Madrid and Valencia (MTS).

Formore information about ArcelorMittal please visit: http://corporate.arcelormittal.com/

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