6-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OFFOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 or15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of January 2024

Commission File Number: 001-14946

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

(Translation of Registrant’s name into English)

AvenidaRicardo Margáin Zozaya #325, Colonia Valle del Campestre

San Pedro Garza García, Nuevo León, 66265México

(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

Cemex announced today that it will report its fourth quarter 2023 results on Thursday, February 8, 2024, and host a conference call and a live audio webcast presentation to discuss the results on that same date at 10:00 a.m. U.S. Eastern Time (09:00 a.m. Mexico Central Time). Cemex’s live presentation can be accessed, and dial-in information is available, at www.cemex.com.

WhileCemex does not expect any issues during Cemex’s fourth quarter 2023 results conference call and audio webcast presentation, we may experience technical difficulties or interruptions that might arise due to unforeseen events or issues beyondCemex’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. However, all materials related to Cemex’s fourth quarter 2023 results, which willinclude relevant information, are expected to be posted in Cemex´s website (www.cemex.com) and filed with the Mexican Stock Exchange (Bolsa Mexicana de Valores) and U.S. Securities and Exchange Commission before the conference call and audiowebcast presentation.

Except as the context otherwise may require, references in this report to “Cemex,” “we,” “us,”“our,” and other similar references are to Cemex, S.A.B. de C.V. (NYSE: CX) and its consolidated subsidiaries. The information to be disclosed in the reports, presentations, and documents and the current or future events referenced hereinmay contain forward-looking statements within the meaning of the U.S. federal securities laws. We intend these forward-looking statements to be covered by the safe harbor provisions for forward-looking statements within the meaning of the U.S.federal securities laws. These forward-looking statements and information are necessarily subject to risks, uncertainties, and assumptions, including but not limited to statements related to Cemex’s plans, objectives, estimates and expectations(financial or otherwise), and typically can be identified by the use of words such as “may,” “assume,” “might,” “should,” “could,” “continue,” “would,” “can,”“consider,” “anticipate,” “estimate,” “expect,” “envision,” “plan,” “believe,” “foresee,” “predict,” “potential,” “target,”“strategy,” “intend,” “aimed”, or other similar terms. Although Cemex believes that its expectations as of the date made are reasonable, it can give no assurance that these expectations will prove to be correct, andactual results may vary materially from historical results or results anticipated, expected or projected by forward-looking statements due to various factors. These forward-looking statements reflect, as of the date on which such forward-lookingstatements are made, or unless otherwise indicated, our current estimates, expectations and projections about future events based on our knowledge of present facts and circumstances and assumptions about future events. These statements necessarilyinvolve risks, uncertainties, and assumptions that could cause actual results to differ materially from historical results or those anticipated in the reports and documents to be disclosed in the events referenced in this report. Among others, suchrisks, uncertainties, and assumptions that could cause results to differ, or that otherwise could have an impact on us, include those discussed in Cemex’s most recent annual report and those detailed from time to time in Cemex’s otherfilings with the Securities and Exchange Commission and the Mexican Stock Exchange (Bolsa Mexicana de Valores), which factors are incorporated herein by reference, including, but not limited to: impact of pandemics, epidemics or outbreaks ofinfectious diseases and the response to any such event by governments and other third parties, which could adversely affect, among other matters, the ability of our operating facilities to operate at full or any capacity, supply chains,international operations, availability of liquidity, investor confidence and consumer spending, as well as the availability of, and demand for, our products and services; the cyclical activity of the construction sector; our exposure to othersectors that impact our and our clients’ businesses, such as, but not limited to, the energy sector; availability of raw materials and related fluctuating prices of raw materials, as well as of goods and services in general, in particularincreases in prices as a result of inflation; volatility in pension plan asset values and liabilities, which may require cash or asset contributions to the pension plans; the impact of environmental cleanup costs and other remedial actions, andother liabilities relating to existing and/or divested businesses; our ability to secure and permit aggregates reserves in strategically located areas or to increase our aggregates reserves; the timing and amount of federal, state and local fundingfor infrastructure; changes in the level of spending for private residential and private nonresidential construction; changes in our effective tax rate; competition in the markets in which we offer our products and services; general political,social, health, economic and business conditions in the markets in which we operate or that affect our operations and any significant economic, health, political or social developments in those markets, as well as any inherent risks to internationaloperations; the regulatory environment, including energy, tax, labor, antitrust, and acquisition-related rules and regulations, as well as the increasing regulations related to environmental and social compliance; our ability to satisfy ourobligations under our material debt agreements, the indentures that govern our outstanding notes, and other debt instruments and financial obligations, including our subordinated notes with no fixed maturity; the availability of short-term creditlines or working capital facilities, which can assist us in connection with market cycles; the impact of our below investment grade debt rating on our cost of capital and on the cost of the products and services we purchase; loss of reputation ofour brands; our ability to consummate asset sales, fully integrate newly acquired businesses, achieve cost-savings from our cost-reduction initiatives, implement our pricing initiatives for our products and generally meet our business strategygoals; the increasing reliance on information technology infrastructure for our sales, logistics, invoicing, procurement, financial statements and other processes that can adversely affect our sales and operations in the event that theinfrastructure does not work as intended, experiences technical difficulties or is subjected to cyber-attacks; changes in the economy that affect the demand for consumer goods, consequently affecting demand for our products and services; climatechange, in

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.