Westlake Corporation (NYSE: WLK) announced today that its Westlake Epoxy Duisburg, Germany manufacturing site has received the International Sustainability & Carbon Plus (ISCC PLUS) certification. The site received mass balance certification for its tracing and handling of sustainable materials in the production of epoxy specialty products. This is the second Westlake Epoxy site in Europe to receive ISCC PLUS certification. The goal is to achieve this certification for all Westlake Epoxy sites in Europe in the near future. “This marks a significant step in Westlake Epoxy’s strategy to integrate renewable carbon materials into its raw material supply chain while reducing energy consumption and greenhouse gas emissions,” said Ann Frederix, Vice President - Epoxy. “The ISCC PLUS certification creates opportunities for our customers to access a wider range of innovative, renewable attributed and lower-carbon footprint products. The mass balancing concept ensures equivalent performance

Record Housing and Infrastructure Products (HIP) annual income from operations of $710 million with a 17% income from operations margin and a 23% EBITDA margin Generated $2.3 billion of net cash from operating activities and $1.3 billion of free cash flow in 2023 Performance and Essential Materials (PEM) results impacted by Identified Items totaling $625 million Westlake Corporation (NYSE: WLK) (the "Company" or "Westlake") today announced fourth quarter and full year 2023 results. SUMMARY FINANCIAL HIGHLIGHTS ($ in millions except per share data and percentages)       Three Months Ended   Twelve Months Ended     December 31,   September 30,   December 31,   December 31,     2023   2023   2022   2023   2022 Westlake Corporation                     Net sales   $ 2,826     $ 3,115     $ 3,299     $ 12,548     $ 15,794

Record Housing and Infrastructure Products (HIP) annual income from operations of $710 million with a 17% income from operations margin and a 23% EBITDA margin Generated $2.3 billion of net cash from operating activities and $1.3 billion of free cash flow in 2023 Performance and Essential Materials (PEM) results impacted by Identified Items totaling $625 million Westlake Corporation (NYSE: WLK) (the "Company" or "Westlake") today announced fourth quarter and full year 2023 results. SUMMARY FINANCIAL HIGHLIGHTS ($ in millions except per share data and percentages) Three Months Ended Twelve Months Ended December 31, September 30, December 31, December 31, 2023 2023 2022 2023 2022 Westlake Corporation Net sales $ 2,826 $ 3,115 $ 3,299 $ 12,548 $ 15,794 Income (loss) from operations

$0.50 per share dividend declared payable on March 14, 2024 The Board of Directors of Westlake Corporation (NYSE: WLK) today declared a regular dividend distribution of 50 cents per share for the fourth quarter of 2024. This dividend will be payable on March 14, 2024, to stockholders of record on February 28, 2024. This is the 78th successive quarterly dividend that Westlake has declared since completing its initial public offering in August 2004. The statements in this release that are not historical facts, including statements regarding future repurchases of common stock, are forward-looking statements. These forward-looking statements are subject to significant risks and uncertainties. Actual results could differ materially, based on factors including, but not limited to, the ultimate timing, outcome and results of integrating the operations of recent acquisitions; general economic and business conditions; the cyclical nature of the chemical and building products industries;

Westlake Corporation (NYSE: WLK) will release its fourth quarter and full year 2023 earnings prior to the market opening on Tuesday, February 20, 2024. The company will host a conference call at 11:00 a.m. Eastern Time (10:00 a.m. Central Time) on the same day to discuss the earnings release. To access the conference by phone, it is necessary to pre-register at https://register.vevent.com/register/BIb0686f53c7f44babb49b408c59ec0d23 . Once registered, you will receive a phone number and unique PIN number. When you dial in, you will input the PIN number to be placed into the call. The conference call and replay will be available via webcast at https://edge.media-server.com/mmc/p/fg9k946y and the earnings release can be obtained via the company’s Web page at https://investors.westlake.com/news/default.aspx . About Westlake: Westlake is a global manufacturer and supplier of materials and innovative products that enhance life every day. Headquartered in Houston, with operations in Asia,

Westlake Chemical Partners (NYSE: WLKP) will release its fourth quarter and full year 2023 earnings prior to the market opening on Tuesday, February 20, 2024. The company will host a conference call at 1:00 p.m. Eastern Time (12:00 p.m. Central Time) on the same day to discuss the earnings release. To access the conference by phone, it is necessary to pre-register at https://register.vevent.com/register/BI4edd1a6cc9e749b585fb66878269ae6f . Once registered, you will receive a phone number and unique PIN number. When you dial in, you will input the PIN number to be placed into the call. The conference call and replay will be available via webcast at https://edge.media-server.com/mmc/p/gwkvbr9r and the earnings release can be obtained via the company's Web page at, https://investors.wlkpartners.com/corporate-profile/default.aspx . About Westlake Chemical Partners: Westlake Chemical Partners is a limited partnership formed by Westlake Corporation to operate, acquire and develop ethylene

$0.4714 per unit distribution declared payable on February 20, 2024 The Board of Directors of Westlake Chemical Partners GP LLC, the general partner of Westlake Chemical Partners LP (the "Partnership") (NYSE:WLKP), has declared a distribution of $0.4714 per unit. This is the 38th quarterly distribution announced by the Partnership since its initial public offering. The distribution will be payable on February 20, 2024, to unit holders of record on February 2, 2024. This release is intended to be a qualified notice under Treasury Regulation Section 1.1446-4(b). Brokers and nominees should treat one hundred percent (100.0%) of the Partnership’s distributions to non-U.S. investors as being attributable to income that is effectively connected with a United States trade or business. Accordingly, the Partnership’s distributions to non-U.S. investors are subject to federal income tax withholding at the highest applicable effective tax rate. About Westlake Chemical Partners LP Westlake

Westlake Global Compounds, a leading provider of PVC compounds, is combining its sustainability efforts with Westlake Dimex, a leading recycler of industrial PVC. This collaboration will leverage Westlake Global Compounds' expertise in PVC compounds with Westlake Dimex's expertise in recycled materials, helping Westlake Global Compounds in its efforts to reduce waste and its environmental impact. "Westlake Global Compounds and Westlake Dimex will continue our efforts to reduce our environmental footprint and expand our participation in recycling and investment in products that contribute to sustainability,” said Renee Havrilla, vice president of Westlake Global Compounds and Westlake Dimex. The partnership will focus on the reprocessing of Westlake Global Compounds’ materials and toll processing services offered by Westlake Dimex, including grinding, shredding, blending and compounding. Westlake Dimex has achieved nine GreenCircle Certified Recycled Content certifications, covering