UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 or 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of September, 2021

Commission File Number: 001-14946

CEMEX, S.A.B. de C.V.

(Translation of Registrant’s name into English)

Avenida Ricardo Margáin Zozaya #325, Colonia Valle del Campestre,

San Pedro Garza García, Nuevo León 66265, México

(Address of principal executive offices)

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

Form 20-F  ☒            Form 40-F  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

Contents

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, CEMEX, S.A.B. de C.V. has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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EXHIBIT INDEX

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Exhibit 1

CEMEX TO PROVIDE UPDATE ON REGIONAL BUSINESSES AND

CLIMATE ACTION STRATEGY AT CEMEX DAY ON OCTOBER 7, 2021

MONTERREY, MEXICO. SEPTEMBER 30, 2021 – CEMEX, S.A.B. de C.V. (“CEMEX”) (NYSE: CX) announced today that it will host the second part of its 2021 CEMEX Day on Thursday October 7, 2021 at 9:00 am ET. The event will be available to the public via a live video webcast presentation.

The presentation will include an update from the regional presidents, the drivers of their business and the outlook of their respective regions. The regional heads include:

Additionally:

A detailed agenda for this event as well as the live video webcast can be accessed at: www.cemex.com/cemex-day-part2-2021

A replay of the video webcast will be available for two weeks after the event.

CEMEX is a global construction materials company that is building a better future through sustainable products and solutions. CEMEX is committed to achieving carbon neutrality through relentless innovation and industry-leading research and development. CEMEX is at the forefront of the circular economy in the construction value chain and is pioneering ways to increase the use of waste and residues as alternative raw materials and fuels in its operations with the use of new technologies. CEMEX offers cement, ready-mix concrete, aggregates, and urbanization solutions in growing markets around the world, powered by a multinational workforce focused on providing a superior customer experience, enabled by digital technologies. For more information, please visit: www.cemex.com

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This presentation is to include information that could be relevant to CEMEX investors. While CEMEX does not expect any issues during the event on October 7th, 2021 announced in this press release, we may experience technical difficulties or interruptions that might arise due to issues beyond CEMEX’s control including, but not limited to, using certain methods for the conference call and audio webcast that CEMEX may have not used in the past but that CEMEX could use now because of COVID-19 related health and safety protocols and guidelines. However, all written materials related to CEMEX’s October 7^th, 2021 event announced in this press release are expected to be posted in CEMEX´s website (www.cemex.com) and filed with the Mexican Stock Exchange and U.S. Securities and Exchange Commission. The items scheduled to be discussed on the October 7th, 2021 event being announced may change between now and the day of the event. CEMEX assumes no obligation to update or correct the information contained in this press release.

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