6-K

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 January 2026

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

Cemex, S.A.B. de C.V. (“Cemex”) (NYSE: CX) announced today that it will report its fourth quarter 2025 results on Thursday, February 5, 2026, 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.

While Cemex does not expect any issues during Cemex’s fourth quarter 2025 results conference call and audio webcast presentation scheduled forFebruary 5, 2026, we may experience technical difficulties or interruptions that might arise due to unforeseen events or issues beyond Cemex’s control including, but not limited to, using certain methods for the conference call and audiowebcast that Cemex may have not used in the past. All materials related to Cemex’s fourth quarter 2025 results, which will include relevant information, are expected to be posted on Cemex’s website (www.cemex.com) and filed with theMexican National Banking and Securities Commission (Comisión Nacional Bancaria y de Valores, the “CNBV”), Mexican Stock Exchange (Bolsa Mexicana de Valores, the “BMV”) and U.S. Securities and Exchange Commission(“SEC”) before the conference call and audio webcast presentation.

Except as the context otherwise may require, references in thisinvitation to “Cemex,” “we,” “us,” “our,” or similar expressions refer to Cemex, S.A.B. de C.V. (NYSE: CX; BMV: CEMEX.CPO) and its consolidated entities. The following applies to this invitation, thefourth quarter 2025 results conference call, webcast and reports, presentations, and documents presented therein, any oral presentation made therein by Cemex or any person on behalf of Cemex, as well as to any question-and-answer session or related discussion. The information to be disclosed in the conference call and webcast and reports, presentations, and documents presented therein, and the current or futureevents referenced therein may contain forward-looking statements within the meaning of applicable securities laws and regulations, including but not limited to Section 27A of the Securities Act of 1933, as amended, and Section 21E of theSecurities Exchange Act of 1934, as amended. We intend these forward-looking statements to be covered by the “safe harbor” provisions for forward-looking statements within the meaning of applicable securities laws and regulations in alljurisdictions where such provisions exist, including but not limited to the US Private Securities Litigation Reform Act of 1995. 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, and expectations (financial or otherwise), and typically can be identified by the use of words such as, but not limited to, “will,” “may,”“assume,” “might,” “should,” “could,” “continue,” “would,” “can,” “consider,” “anticipate,” “estimate,” “expect,”“envision,” “plan,” “believe,” “foresee,” “predict,” “potential,” “target,” “goal”, “strategy,” “intend,” “aimed”, orother forward-looking words. Unless otherwise indicated, these forward-looking statements reflect our expectations and projections about the future based on certain assumptions and on our knowledge of facts and circumstances as of the date suchforward-looking statements are made. Although Cemex believes that its expectations are reasonable, it can give no assurance that these expectations will prove to be correct, and actual results, performance and/or achievements may vary, includingmaterially, from historical results, performance and/or achievements or those anticipated by forward-looking statements due to various factors. Among others, such risks, uncertainties, assumptions, and other important factors that could causeresults and any estimate, projection and/or guidance presented during the webcast to differ or fail to materialize, or that otherwise could have an impact on us, include those discussed in Cemex’s most recent annual report and those detailedfrom time to time in Cemex’s other filings with the SEC, the CNBV and the BMV, which factors are incorporated herein by reference, including, but not limited to: changes in general economic, political and social conditions, includinggovernment shutdowns, new governments or regimes and decisions implemented by such new governments or regimes, changes in laws or regulations in the countries in which we do business, elections, changes in inflation, interest and foreign exchangerates, employment levels, population growth, any slowdown in the flow of remittances into countries where we operate, consumer confidence and the liquidity of the financial and capital markets in Mexico, the United States of America, the EuropeanUnion (“EU”), the United Kingdom or other countries in which we operate; the cyclical activity of the construction sector and reduced construction activity in our end markets or reduced use in our end markets for our products; ourexposure to sectors that impact our and our clients’ businesses, particularly those operating in the commercial and residential construction sectors, and the public and private infrastructure and energy sectors; volatility in pension planasset values and liabilities, which may require cash or other contributions to the pension plans; changes in spending levels for residential and commercial construction and general infrastructure projects; the availability of short-term credit linesor working capital facilities, which can assist us in connection with market cycles; any impact of not maintaining investment grade debt rating or not obtaining investment grade debt ratings from additional rating agencies on our cost of capital andon the cost of the products and services we purchase; availability of raw materials and related fluctuating prices of raw materials, as well as of goods and services in general, in particular increases in prices of raw materials, goods and services,as a result of inflation, trade barriers, measures imposed by governments or as a result of conflicts between countries that disrupt supply chains; our ability to maintain and expand our distribution network and maintain favorable relationships withthird parties who supply us with equipment, services and essential suppliers; competition in the markets in which we offer our products and services; the impact of environmental cleanup costs and other remedial actions, and other environmental,climate and related liabilities relating to existing and/or divested businesses, assets and/or operations; our ability to secure and permit aggregates reserves in strategically located areas in amounts that our operations require to operate oroperate in a cost-efficient manner; the timing and amount of federal, state, and local funding for infrastructure; changes in our effective tax rate; our ability to comply with regulations and implement technologies and other initiatives that aim toreduce and/or capture CO2 emissions and comply with related carbon emissions regulations in place in the jurisdictions where we have operations; the legal and regulatory environment, including environmental, climate, trade, energy, tax, antitrust,sanctions, export controls, construction, human rights and labor welfare, and acquisition-related rules and regulations in the countries and regions in which we have operations; the effects of currency fluctuations on our results of operations andfinancial condition; our ability to satisfy our obligations under our debt agreements, the indentures that govern our outstanding notes, and our other debt instruments and financial obligations, and also regarding our subordinated notes with nofixed maturity and other financial obligations; adverse legal or regulatory proceedings or disputes, such as class actions or enforcement or other proceedings brought by third

measure of financial position under IFRS, Operating EBITDA is the financial measure used by Cemex’smanagement to review operating performance and profitability, for decision-making purposes and to allocate resources. Moreover, our Operating EBITDA is a measure used by Cemex’s creditors to review our ability to internally fund capitalexpenditures, service or incur debt and comply with financial covenants under our financing agreements. Furthermore, Cemex’s management regularly reviews our Operating EBITDA Margin by reportable segment and on a consolidated basis as ameasure of performance and profitability. These non-IFRS financial measures do not have any standardized meaning and are therefore unlikely to be comparable to similarly titled measures presented by othercompanies. The financial measures presented in the reports, presentations, and documents to be disclosed during Cemex’s fourth quarter 2025 results conference call and audio webcast presentation are being provided for informative purposes onlyand shall not be construed as investment, financial, or other advice.

Also, the reports, presentations, and documents to be disclosed duringCemex’s fourth quarter 2025 results conference call and audio webcast presentation include statistical data regarding the production, distribution, marketing and sale of cement, ready-mix concrete,clinker, aggregates, and Urbanization Solutions. Cemex generated some of this data internally, and some was obtained from independent industry publications and reports that Cemex believes to be reliable sources. Cemex has not independently verifiedthis data nor sought the consent of any organization to refer to their reports in the reports, presentations, and documents to be disclosed in the events referenced herein. Cemex acts in strict compliance with antitrust laws and as such, among othermeasures, maintains an independent pricing policy that has been independently developed and its core element is to price Cemex’s products and services based upon their quality and characteristics as well as their value to Cemex’scustomers. Cemex does not accept any communications or agreements of any type with competitors regarding the determination of Cemex’s prices for Cemex’s products and services. Unless the context indicates otherwise, all references topricing initiatives, price increases or decreases, refer to Cemex’s prices for Cemex’s products.

The information, statements, andopinions contained in the reports, presentations, and documents to be disclosed during Cemex’s fourth quarter 2025 results conference call and audio webcast presentation are for informational purposes only and do not constitute a public offerunder any applicable legislation, an offer to sell, or solicitation of any offer to buy any securities or financial instruments, or any advice or recommendation with respect to such securities or other financial instruments. You should not construeany such information or other material as legal, tax, investment, financial, or other advice. Cemex is not responsible for any third-party information referenced.

Cautionary Statement Regarding Environmental, Social, and Governance (“ESG”) and Sustainability-Related Data, Metrics, and Methodologies

The reports, presentations, and documents to be disclosed during Cemex’s fourth quarter 2025 results conference call and audio webcastpresentation include non-financial metrics, estimates, or other information related to ESG and sustainability matters that are subject to significant uncertainties, which may include the methodology,collection, and verification of data, various estimates, and assumptions, and/or underlying data that is obtained from third parties, some of which cannot be independently verified.

The preparation of certain information on ESG and sustainability matters contained in the reports, presentations, and documents to be disclosed duringCemex’s fourth quarter 2025 results conference call and audio webcast presentation requires the application of a number of key judgments, assumptions, and estimates. The reported measures reflect good faith estimates, assumptions, andjudgments at the given point in time. There is a risk that these judgments, estimates, or assumptions may subsequently prove to be incorrect and/or, to the extent legally required, may need to be restated or changed. The disclosure of information onsustainability-related matters is not yet subject to the same recognized or accepted reporting or accounting principles and rules as traditional financial information. Consequently, there are no commonlyaccepted reporting practices for us to follow, and ESG metrics among organizations in our industry may not be comparable. In addition, the underlying data, systems, and controls that support non-financialreporting are generally considerably less sophisticated than the systems and internal control for financial reporting and rely on manual processes. This may result in non-comparable information betweenorganizations and/or between reporting periods within organizations as methodologies continue to develop and/or be socialized. The further development of or changes to accounting and/or reporting standards could materially impact the performancemetrics, data points, and targets contained in the reports, presentations, and documents to be disclosed during Cemex’s fourth quarter 2025 results conference call and audio webcast presentation, and the reader may not be able to compare non-financial information performance metrics, data points, or targets between reporting periods on a direct like-for-like basis.

Additionally, the information to be disclosed in the reports and documents during Cemex’s fourth quarter 2025 results conference call andaudio webcast presentation contain references to “green,” “social,” “sustainable,” or equivalent-labelled activities, products, assets, or projects. There is currently no single globally recognized or accepted,consistent, and comparable set of definitions or standards (legal, regulatory, or otherwise) of, nor widespread cross-market consensus i) as to what constitutes, a “green”, “social”, or “sustainable” or havingequivalent-labelled activity, product, or asset; or ii) as to what precise attributes are required for a particular activity, product, or asset to be defined as “green”, “social”, or “sustainable” or such otherequivalent label; or iii) as to climate and sustainable funding and financing activities and their classification and reporting. Therefore, there is little certainty, and no assurance or representation is given that our activities, products, orassets and/or reporting of such activities and/or reporting of those activities, products, or assets will meet any present or future expectations or requirements for describing or classifying such activities, products, or assets as“green”, “social”, or “sustainable” or attributing similar labels. We expect policies, regulatory requirements, standards, and definitions to be developed and continuously evolve over time.

Cautionary Statement Regarding Forward-Looking ESG or Sustainability Statements

Certain sections in the reports, presentations, and documents to be disclosed during Cemex’s fourth quarter 2025 results conference call and audiowebcast presentation contain ESG- or sustainability-related forward-looking statements, such as aims, ambitions, estimates, forecasts, plans, projections, targets, goals and other metrics, including but notlimited to: climate and emissions, business and human rights, corporate governance, research and development and partnerships, development of products and services that intend to address sustainability-related concerns and sustainability relatedtargets/ ambitions when finalized, including the implementation of technologies and other initiatives that aim to reduce and/or capture CO2 emissions. These forward-looking statements also include references to specific programs, such as our

current “Future in Action” climate action program, as well as various ESG-related indicators, objectives or metrics disclosed previously or that may be disclosed in the future, none of which are guarantees and any and all of which may ultimately not be achieved or may be abandoned atany time, whether in part, in full, or within any specific timeframe. There are many significant uncertainties, assumptions, judgements, opinions, estimates, forecasts and statements made of future expectations underlying these forward-lookingstatements which could cause actual results, performance, outcomes or events to differ materially from those expressed or implied in these forward-looking statements, which include, but are not limited to: the extent and pace of climate change,including the timing and manifestation of physical and transition risks; the macroeconomic environment; uncertainty around future climate-related policy, including the timely implementation and integration of adequate government policies; theeffectiveness of actions of governments, legislators, regulators, businesses, investors, customers, and other stakeholders to mitigate the impact of climate and sustainability-related risks; changes in customer behavior and demand, changes in theavailable technology for mitigation and the effectiveness of any such technologies, as some of these new technologies may be unproven; excessive costs and expenses related to acquire and/or develop technology for mitigation; the roll-out of low carbon infrastructure; the availability and adoption of renewable energy in our value chain; the development of carbon capture, circular utilization, and sequestration technologies, including theadoption of cost-effective carbon-related technologies such as carbon capture, utilization, and storage; the availability of accurate, verifiable, reliable, consistent, and comparable climate-related data; lack of transparency and comparability ofclimate-related forward-looking methodologies; variation in approaches and outcomes, as variations in methodologies may lead to under or overestimates and consequently present exaggerated indication of climate-related risk; and reliance onassumptions and future uncertainty. Calculations of forward-looking metrics are complex and require many methodological choices and assumptions.

Accordingly, undue reliance should not be placed on these forward-looking statements. Furthermore, changing national and international standards, industryand scientific practices, regulatory requirements, and market expectations regarding climate change, which remain under continuous development, are subject to different interpretations.

There can be no assurance that these standards, practices, requirements, and expectations will not be interpreted differently than our understanding whendefining sustainability-related ambitions and targets or change in a manner that substantially increases the cost or effort for us to achieve such ambitions and targets.

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.