Celanese Corp

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

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CELANESE CORPORATION

(Name of Registrant as Specified In Its Charter)

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Table of Contents

Cautionary Note Regarding Forward-Looking Statements; Available InformationThis Proxy Statement includes estimates, projections, statements relating to our business plans, objectives, and expected operating results that are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933, and Section 21E of the Securities Exchange Act of 1934. Forward-looking statements may appear throughout this Proxy Statement. These forward-looking statements generally are identified by the words “believe,” “project,” “expect,” “anticipate,” “estimate,” “intend,” “strategy,” “future,” “opportunity,” “plan,” “may,” “should,” “will,” “would,” “will be,” “will continue,” “will likely result,” and similar expressions. Forward-looking statements are based on current expectations and assumptions that are subject to risks and uncertainties that may cause actual results to differ materially. We describe risks and uncertainties that could cause actual results and events to differ materially in “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” sections of our Forms 10-K and 10-Q. We undertake no obligation to update or revise publicly any forward-looking statements, whether because of new information, future events, or otherwise.References to our website in this Proxy Statement are provided as a convenience, and the information on our website is not, and shall not be deemed to be a part of this Proxy Statement or incorporated into any other filings we make with the SEC. The SEC maintains a website that contains reports, proxy and information statements, and other information regarding issuers, including Celanese Corporation, that electronically file with the SEC at http://www.sec.gov.

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A Message from Lori J. Ryerkerk, our Chair and CEOand William M. Brown, our Lead Independent Director

DEAR FELLOW SHAREHOLDERS:

We are pleased to write to you in advance of our upcoming Annual Meeting of Shareholders. Celanese faced a challenging year in 2023, a year in which our industry faced cyclical demand downturns and prolonged destocking in the supply chain where we sell our products, both of which led to significant pricing and volume challenges.

In the face of these challenges, our Board and our teams focused on building upon and strengthening our solid foundation and executing controllable actions to create value now and into the future. We would like to reflect on three key priorities of our Board.

Build and Execute

Our strategic priorities in 2023 included (i) continuing to lift our foundational level of earnings, (ii) integrating and driving synergy capture from the Mobility and Materials (M&M) acquisition and (iii) generating cash to support our commitment to rapid deleveraging.

Our leadership and broader teams worked with vigor and urgency to achieve the objectives to further these priorities. We worked to optimize our global manufacturing footprint, significantly improved year-over-year stewardship performance, upgraded our company-wide enterprise resource planning system to drive productivity, and exceeded our 2023 net debt reduction objectives. You can read more about these efforts in “Performance Highlights” in the Proxy Summary.

While we are proud of the results the Celanese team has achieved, we look forward to continuing our efforts in 2024 and beyond as there is still much more to do.

Advance our Sustainability Strategy

Our leadership team, with guidance and oversight by our Board, continues to thoughtfully and intentionally advance our sustainability strategy. We have worked together to identify and act on business opportunities, to carefully address our risks and to communicate our plans to our investors and other stakeholders.

We are actively developing product opportunities to help global customers meet the growing demand for more sustainable and circular solutions. Recently we launched a large carbon capture and utilization (CCU) project to support low-carbon solutions and announced a collaboration to develop a new fiber for performance stretch fabrics using recyclable polymers. These efforts deepen our portfolio of sustainable solutions and expand our value chain.

We have also advanced our commitment to develop our strategy regarding Scope 3 greenhouse gas emissions. We are implementing Scope 3 reporting capability and integrating the M&M business into our reporting to prepare for future disclosure.

You can find more in “Sustainability Highlights” in the Proxy Summary.

Strengthen the Board for Long-Term Value

Our Board represents a variety of viewpoints, experience and professional qualifications all as described in ”Item 1: Election of Directors — Director Nominees.” Board composition is an ongoing priority, and over the last few years, the Board has intentionally sought to deepen its perspectives in complex global manufacturing by adding currently serving executives of large global manufacturers to its ranks. Our three most recently elected directors fit this profile, and complement the broad and diverse skillsets of the Board.

The Board remains committed to thoughtful, intentional and long-term succession planning to enhance its ability to serve long-term shareholder value. The Board would also like to recognize the contributions of Jean S. Blackwell, who will be retiring from the Board after more than ten years of service, and William M. Brown, who has been appointed Chief Executive Officer of 3M Company and will depart from the Board after more than eight years of service. The Board thanks each of them and wishes them well.

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A Message from Lori J. Ryerkerk, our Chair and CEOand William M. Brown, our Lead Independent Director

Looking Ahead

U.S. First Lady Eleanor Roosevelt once said, “The world of the future is in our making. Tomorrow is now.” Celanese leaders remain focused on controllable actions that will ensure we are well positioned to take advantage of growth potential.

Please join our Board of Directors and executive officers on May 13, 2024, at 11:30 a.m. Central time, when we hold our Annual Meeting of Shareholders in live virtual format. Your vote is very important, and whether or not you are able to attend the event in real time, we encourage you submit your voting instructions by proxy as described in this document. We look forward to your participation.

Thank you for your continued support of Celanese.

Sincerely,

Celanese 2024 / Notice of Annual Meeting and Proxy Statement / 2

Notice of Annual Meeting of Shareholders

CELANESE CORPORATION

222 W. Las Colinas Blvd., Suite 900N

Irving, Texas 75039

NOTICE OF ANNUAL MEETING OF SHAREHOLDERS

This year’s Annual Meeting will be held as a “virtual meeting” via the Internet at www.virtualshareholdermeeting.com/CE2024. You will be able to vote and submit questions online through the virtual meeting platform during the Annual Meeting.

To ensure that your shares are represented at the meeting, we urge you to submit your voting instructions by proxy as promptly as possible. You may submit your proxy via the Internet or telephone, or, if you received paper copies of the proxy materials by mail, you can also submit a proxy via mail by following the instructions on the proxy card or voting instruction card. We encourage you to submit a proxy via the Internet. It is convenient and saves us significant postage and processing costs. You can revoke a proxy at any time prior to its exercise at the Annual Meeting by following the instructions in the Proxy Statement.

By Order of the Board of Directors of

Celanese Corporation

Michael R. Sullivan

Vice President, Deputy General Counsel

and Corporate Secretary

Irving, Texas

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALSFOR THE ANNUAL MEETING OF SHAREHOLDERS TO BE HELD ON MAY 13, 2024

The Celanese Corporation 2024 Notice of Annual Meeting and Proxy Statement, 2023 Annual Reportand other proxy materials are available at www.proxyvote.com.

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Voting Information

VOTING INFORMATION

You are invited to attend the Annual Meeting to be held at 11:30 a.m. (Central Daylight Saving Time) on Monday, May 13, 2024. This year’s Annual Meeting will be held as a “virtual meeting” via the Internet at www.virtualshareholdermeeting.com/CE2024.

It is very important that you vote in order to play a part in the future of the Company. Please carefully review the proxy materials for the Annual Meeting and follow the instructions below to cast your vote on all of the voting matters.

Who is Eligible to Vote

You are entitled to vote at the Annual Meeting if you were a shareholder at the close of business on March 18, 2024, the record date for the meeting. On the record date, there were 111,563,396 shares of the Company’s Common Stock issued, outstanding and entitled to vote at the Annual Meeting. Each share of Common Stock is entitled to one vote on each proposal to be voted on at the meeting.

How to Vote

Even if you plan to attend the Annual Meeting, please submit your voting instructions by proxy as soon as possible using one of the following methods for submitting a proxy (see page 98 for additional details). Make sure to have your proxy card, voting instruction form or Notice of Internet Availability in hand and follow the instructions provided. Unless those documents provide different instructions, most of our shareholders will be able to vote in advance of the meeting by one of the following means:

• You will need the 16-digit control number included on your proxy card, voting instruction form or Notice of Internet Availability of Proxy Materials.

If you are a shareholder who holds shares through a brokerage firm, bank, trust or other similar organization (that is, in “street name”), please refer to the instructions from the broker or organization holding your shares.

If you have questions or require assistance with voting your shares, or if you need additional copies of the proxy materials, please contact Alliance Advisors, LLC, 200 Broadacres Drive, 3rd Floor, Bloomfield, New Jersey 07003. Shareholders may call toll free: (800) 574-5971.

Important Note About Meeting Admission Requirements: If you plan to attend the virtual meeting, see the answer to question 2 on page 97 for important details on requirements to log-in to the meeting.

Electronic Shareholder Document Delivery

Instead of receiving future copies of annual meeting proxy materials by mail, shareholders of record and most beneficial owners can elect to receive an e-mail that will provide electronic links to these documents. Opting to receive your proxy materials online will save us the cost of producing and mailing documents and will also give you an electronic link to the proxy voting site.

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Proxy Summary

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Proxy Summary

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