Westlake Chemical Partners (NYSE: WLKP) today provided the following information regarding 2023 investor tax reporting: As previously noted in the 2023 Investor Tax Reporting Package for our unitholders’ investment in Westlake Chemical Partners, LP, the Partnership will report items of international tax relevance to our partners on Schedule K-3 for tax year 2023. As we disclosed in our quarterly distribution press releases, all of our income is effectively connected with a United States trade or business. However, a limited number of unitholders (primarily foreign unitholders and unitholders having US international reporting obligations) may need the detailed information disclosed on Schedule K-3 for their specific reporting requirements. Our Schedule K-3 for tax year 2023 is now available online at www.taxpackagesupport.com/WLKP . This information may be necessary in the completion of our unitholders’ tax return. As such we encourage our unitholders to review the information

$0.500 per share dividend declared payable on June 6, 2024 The Board of Directors of Westlake Corporation (NYSE: WLK) today declared a regular dividend distribution of 50 cents per share for the first quarter of 2024. This dividend will be payable on June 6, 2024, to stockholders of record on May 21, 2024. This is the 79th 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 payment of dividend, are forward-looking statements. These forward-looking statements are subject to significant risks and uncertainties. For more detailed information about the factors that could cause actual results to differ materially, please refer to Westlake’s Annual Report on Form 10-K for the year ended December 31, 2023, which was filed with the SEC in February 2024, and Westlake’s Quarterly Report on Form 10-Q for the quarter ended March 31,

Record first quarter Housing and Infrastructure Products (HIP) income from operations of $210 million with a 20% operating income margin HIP EBITDA of $264 million rose 29% year-over-year with a record first quarter EBITDA margin of 25% PEM sales volume grew 3% sequentially from gradual demand recovery with stable average sales prices Westlake Corporation (NYSE: WLK) (the "Company" or "Westlake") today announced first quarter 2024 results. SUMMARY FINANCIAL HIGHLIGHTS (in millions of dollars, except per share data and percentages)       Three Months Ended March 31, 2024   Three Months Ended December 31, 2023   Three Months Ended March 31, 2023 Westlake Corporation             Net sales   $ 2,975     $ 2,826     $ 3,356   Income (loss) from operations   $ 223     $ (552 )   $ 536   Net income (loss) attributable to Westlake Corporation   $ 174     $ (497 )  

Declared quarterly distribution of $0.4714 per unit; 39 th consecutive quarterly distribution Westlake Chemical Partners LP (NYSE: WLKP) (the "Partnership") today reported net income attributable to the Partnership in the first quarter of 2024 of $14.8 million, or $0.42 per limited partner unit, which was in-line with first quarter 2023 net income of $14.9 million. Cash flows from operating activities in the first quarter of 2024 were $104.6 million, a decrease of $40.3 million compared to first quarter 2023 cash flows from operating activities of $144.9 million, due to less favorable working capital changes. For the three months ended March 31, 2024, MLP distributable cash flow was $16.9 million, a decrease of $0.7 million compared to first quarter 2023 MLP distributable cash flow of $17.6 million. The decrease in MLP distributable cash flow and associated trailing twelve-month coverage ratio was primarily due to lower production and sales volume. First quarter 2024 net income

Westlake Corporation (NYSE: WLK), a global manufacturer and supplier of materials and innovative products, will showcase its solutions that enhance your life every day at NPE 2024 in OCCC West Hall Booth 203 ABC, to be held from May 6-10 in Orlando, Florida. “We are excited to participate in NPE 2024 to present our products and sustainable solutions,” said Amy Moore, Vice President, Westlake Polyethylene. “Westlake strives to deliver high-value, essential products for our customers across several sectors — including healthcare, automotive, agriculture and water systems, food packaging, and housing materials. We endeavor to produce and deliver these goods in increasingly sustainable ways.” Under the theme of “Enhancing Your Life Every Day,” three of Westlake’s businesses will showcase their products: Westlake Global Compounds, Westlake Polyethylene and Westlake North American Vinyls. “As a global leader that produces and manufactures essential materials, we understand the critical role

Pool Chemistry Resources Support Summertime Proper Aquatic Chlorination Commercial pools around the country will soon open, ushering in the start of the summer season. In recognition of National Water Safety Month, which began on May 1 st , Westlake Water Solutions, a business unit of Westlake Corporation (NYSE: WLK); and NSF International, a leading public health and safety organization that provides testing and standards, are reminding health inspectors and pool operators about the importance of using properly specified chlorine tablets in their certified sanitizing systems. “Along with the sun and fun that come with commercial water, it is important to properly chlorinate commercial pools with feeder systems that can keep up with degradation of chlorine due to heavy bather loads, rain and the sun’s ultraviolet rays,” said Austin Looper, director, Westlake Water Solutions business. “Organizations like NSF, the U.S. Centers for Disease Control and Prevention and the American

Declared quarterly distribution of $0.4714 per unit; 39 th consecutive quarterly distribution Westlake Chemical Partners LP (NYSE: WLKP) (the "Partnership") today reported net income attributable to the Partnership in the first quarter of 2024 of $14.8 million, or $0.42 per limited partner unit, which was in-line with first quarter 2023 net income of $14.9 million. Cash flows from operating activities in the first quarter of 2024 were $104.6 million, a decrease of $40.3 million compared to first quarter 2023 cash flows from operating activities of $144.9 million, due to less favorable working capital changes. For the three months ended March 31, 2024, MLP distributable cash flow was $16.9 million, a decrease of $0.7 million compared to first quarter 2023 MLP distributable cash flow of $17.6 million. The decrease in MLP distributable cash flow and associated trailing twelve-month coverage ratio was primarily due to lower production and sales volume. First quarter 2024 net income

Record first quarter Housing and Infrastructure Products (HIP) income from operations of $210 million with a 20% operating income margin HIP EBITDA of $264 million rose 29% year-over-year with a record first quarter EBITDA margin of 25% PEM sales volume grew 3% sequentially from gradual demand recovery with stable average sales prices Westlake Corporation (NYSE: WLK) (the "Company" or "Westlake") today announced first quarter 2024 results. SUMMARY FINANCIAL HIGHLIGHTS (in millions of dollars, except per share data and percentages) Three Months Ended March 31, 2024 Three Months Ended December 31, 2023 Three Months Ended March 31, 2023 Westlake Corporation Net sales $ 2,975 $ 2,826 $ 3,356 Income (loss) from operations $ 223 $ (552 ) $ 536 Net income (loss) attributable to Westlake Corporation $ 174 $ (497 ) $ 394 Diluted earnings (loss) per common share $ 1.34 $ (3.86 ) $ 3.05

$0.4714 per unit distribution declared payable on May 29, 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 39th quarterly distribution announced by the Partnership since its initial public offering. The distribution will be payable on May 29, 2024, to unit holders of record on May 13, 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 Chemical Partners is