8-K

WESTLAKE CORP (WLK)

8-K 2026-02-24 For: 2026-02-24
View Original
Added on April 06, 2026

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of

the Securities Exchange Act of 1934

Date of Report (date of earliest event reported): February 24, 2026

Westlake Corporation

(Exact name of registrant as specified in its charter)

Delaware 001-32260 76-0346924
(State or other jurisdiction<br>of incorporation) (Commission File Number) (I.R.S. Employer<br>Identification No.) 2801 Post Oak Boulevard, Suite 600
--- --- ---
Houston, Texas 77056
(Address of principal executive offices) (Zip Code)

Registrant's telephone number, including area code: (713) 960-9111

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s) Name of each exchange on which registered
Common Stock, $0.01 par value WLK The New York Stock Exchange
1.625% Senior Notes due 2029 WLK29 The New York Stock Exchange

Indicate by check mark whether the registrant is an emerging growth company as defined in as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ◻

Item 2.02. Results of Operations and Financial Condition.

On February 24, 2026, Westlake Corporation (the "Company") issued a press release announcing its 2025 fourth quarter and full year results. A copy of the press release is furnished with this Current Report as Exhibit 99.1.

The information furnished pursuant to this Current Report, including Exhibit 99.1, shall not be deemed to be "filed" for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, and will not be incorporated by reference into any registration statement filed by Westlake Corporation under the Securities Act of 1933, as amended, unless specifically identified as being incorporated therein.

Item 7.01. Regulation FD Disclosure.

The Company is holding a conference call on February 24, 2026 to discuss its 2025 fourth quarter and full year results. Information about the call can be found in the press release furnished with this Current Report as Exhibit 99.1. In addition, the Company made available an investor presentation regarding its 2025 fourth quarter and full year results, which is furnished with this Current Report as Exhibit 99.2.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

The following exhibits are furnished herewith:

99.1    Press release issued on February 24, 2026.

99.2    Investor Presentation.

104    The cover page from this Current Report on Form 8-K, formatted in Inline XBRL.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

WESTLAKE CORPORATION
Date: February 24, 2026 By: /S/ JEAN-MARC GILSON
Jean-Marc Gilson<br><br>President, Chief Executive Officer and Director

Document

EXHIBIT 99.1

WESTLAKE CORPORATION

Contact—(713) 960-9111

Investors—Steve Bender

Media—L. Benjamin Ederington

Westlake Corporation Reports Fourth Quarter and Full Year 2025 Results

•Meaningful actions taken in 2025 to optimize footprint, improve plant reliability, and structurally reduce costs expected to provide earnings improvement in 2026

HOUSTON--(BUSINESS WIRE)--Westlake Corporation (NYSE: WLK) (the "Company" or "Westlake") today announced fourth quarter and full year 2025 results.

i

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,
2025 2025 2024 2025 2024
Westlake Corporation
Net sales $ 2,533 $ 2,838 $ 2,843 $ 11,170 $ 12,142
Income (loss) from operations $ (671) $ (766) $ 66 $ (1,578) $ 875
Net income (loss) attributable to Westlake Corporation (1) $ (544) $ (782) $ 7 $ (1,508) $ 602
Diluted earnings (loss) per common share (1) $ (4.22) $ (6.06) $ 0.06 $ (11.70) $ 4.64
Identified Items (2) $ 511 $ 744 $ $ 1,392 $ 75
Net income (loss) attributable to Westlake Corporation excl. Identified Items $ (33) $ (38) $ 7 $ (116) $ 677
Diluted earnings (loss) per common share excl. Identified Items $ (0.25) $ (0.29) $ 0.06 $ (0.90) $ 5.22
EBITDA $ (315) $ (431) $ 416 $ (248) $ 2,211
EBITDA excl. Identified Items $ 196 $ 313 $ 416 $ 1,144 $ 2,286
EBITDA margin (3) 8% 11% 15% 10% 19%
Housing and Infrastructure Products ("HIP") Segment
Net sales $ 901 $ 1,091 $ 981 $ 4,148 $ 4,317
Income from operations $ 66 $ 151 $ 129 $ 587 $ 807
EBITDA $ 130 $ 215 $ 188 $ 823 $ 1,050
Identified Items (2) $ 16 $ $ $ 16 $
EBITDA excl. Identified Items $ 146 $ 215 $ 188 $ 839 $ 1,050
EBITDA margin (3) 16% 20 % 19% 20% 24%
Performance and Essential Materials ("PEM") Segment
Net sales $ 1,632 $ 1,747 $ 1,862 $ 7,022 $ 7,825
Income (loss) from operations $ (717) $ (902) $ (41) $ (2,100) $ 129
EBITDA $ (450) $ (654) $ 220 $ (1,109) $ 1,086
Identified Items (2) $ 495 $ 744 $ $ 1,376 $ 75
EBITDA excl. Identified Items $ 45 $ 90 $ 220 $ 267 $ 1,161
EBITDA margin (3) 3% 5% 12% 4% 15%

ii

______________________________

(1)Includes $45 million ($0.35 per share) one-time non-cash charge related to changes in Louisiana tax law in the fourth quarter and full year 2024

(2)For the fourth quarter and full year 2025, Identified Items include $495 million of PEM shutdown expenses (as defined below) and $16 million for HIP restructuring expenses (as defined below). Identified Items for the full year 2025 also include a $727 million charge for the write-off of all the goodwill associated with the North American Chlorovinyls reporting unit and $139 million of accrued expenses and $15 million inventory write-off related to previously-announced facility shutdowns. Identified Items for full year 2024 include $75 million of accrued expenses related to previously-announced facility shutdowns.

(3)Excludes Identified Items

BUSINESS HIGHLIGHTS

In the fourth quarter of 2025, Westlake reported net sales of $2.5 billion, a net loss of $544 million, or $4.22 per share, and EBITDA (earnings before interest expense, income taxes, depreciation and amortization) of ($315) million. Earnings in the fourth quarter were impacted by $393 million of charges related to the shutdown of three North American chlorovinyls plants and one styrene plant and $102 million of accrued expenses related to the Pernis shutdown (together, "PEM shutdown expenses") as well as $16 million of restructuring and related expenses in our HIP segment ("HIP restructuring expenses") for a combined $511 million impact ("the Identified Items"). Excluding the effects of the Identified Items, the net loss in the fourth quarter of 2025 was $33 million, or $0.25 per share, and EBITDA was $196 million.

Excluding the Identified Items, for the full year of 2025 Westlake reported net sales of $11.2 billion, a net loss of $116 million, or $0.90 per share and EBITDA of $1.1 billion. Compared to the prior-year financial results, the Company's 2025 results were impacted by lower average sales price, particularly in PEM, lower sales volume, and higher feedstock and energy costs.

Westlake's fourth quarter of 2025 sales decreased 11% year-over-year, driven by a 7% decline in sales volume and a 4% decline in average sales price. Housing and Infrastructure Products sales decreased 8%, driven by an 8% decline in sales volume and unchanged average sales price. Performance and Essential Materials sales decreased 12% over the same period of time, driven by a 7% decline in sales volume and a 5% decline in average sales price.

EXECUTIVE COMMENTARY

"As 2025 came to a close, our PEM profitability improvement plan began to generate tangible benefits with accelerating realization of our cost savings initiatives and significant strategic action to optimize our North American footprint. As a result, PEM's EBITDA for the fourth quarter of 2025 exceeded our expectations while HIP's fourth quarter EBITDA was in-line with our expectations, which reflected the effects of slower housing starts and seasonal weather impacts," said Jean-Marc Gilson, President and Chief Executive Officer.

"For 2026 our priority is to achieve the PEM profitability improvement plan's targeted $600 million in EBITDA improvement while growing HIP's sales and earnings, which are expected to benefit from the January 2026 acquisition of ACI. We are not expecting macroeconomic conditions to be a tailwind to our 2026 goals as global industrial and manufacturing activity remains challenging. However, we are very confident in the ability of our PEM profitability improvement plan to improve earnings in 2026 and we remain well positioned to capitalize on an eventual recovery in global demand," concluded Mr. Gilson.

RESULTS

Consolidated Results

(Unless otherwise noted the financial numbers below exclude the effects of the Identified Items)

For the three months ended December 31, 2025, the Company reported a quarterly net loss of $33 million, or $0.25 per share, on sales of $2.5 billion compared to the net loss of $38 million reported in the third quarter of 2025. Sequentially, earnings were impacted by lower average sales price, particularly in the PEM segment, and lower sales volume, particularly in the HIP segment.

iii

The fourth quarter of 2025 net loss of $33 million was $40 million below the fourth quarter of 2024 primarily due to the 11% decline in Westlake's net sales and higher feedstock and energy costs in the PEM segment.

EBITDA of $196 million for the fourth quarter of 2025 decreased by $220 million compared to fourth quarter 2024 EBITDA of $416 million. Fourth quarter 2025 EBITDA decreased by $117 million compared to third quarter 2025 EBITDA of $313 million.

The full year of 2025 net loss of $116 million was $793 million below the full year of 2024 net income of $677 million. Loss from operations of $186 million for the full year of 2025 decreased by $1.1 billion as compared to income from operations of $1.0 billion for the full year of 2024. The decreases in net income and income from operations were primarily due to lower average sales price, particularly in the PEM segment, lower sales volume, higher feedstock and energy costs, and a more significant impact from planned turnarounds and unplanned outages in 2025.

A reconciliation of EBITDA and net income to EBITDA excluding Identified Items and net income excluding Identified Items as well as a reconciliation of EBITDA to net income, income from operations (including and excluding Identified Items) and net cash provided by operating activities as well as a reconciliation of free cash flow to net cash flow provided by operating activities can be found in the financial schedules at the end of this press release.

PEM shutdown expenses and HIP restructuring expenses ("Identified Items")

As previously announced, during the fourth quarter of 2025 the Company simplified and optimized operations by shutting down three chlorovinyl production facilities and one styrene facility in North America. As a result of these shutdowns, during the fourth quarter of 2025 PEM accrued $386 million of expenses primarily consisting of noncash accelerated depreciation, amortization, and asset write-off charges, and realized a $7 million expense to write-off inventory (recorded in cost of sales). During the fourth quarter of 2025, PEM also accrued $102 million of expenses related to the previously-announced shutdown of the Company's epoxy site at Pernis, The Netherlands. Additionally, during the fourth quarter of 2025 HIP accrued $13 million of expenses for footprint optimization actions and recognized a $3 million loss on the sale of a compounding business (recorded in other income, net).

Cash, Investments and Debt

Net cash provided by operating activities was $225 million for the fourth quarter of 2025 and capital expenditures were $241 million. As of December 31, 2025, cash, cash equivalents and fixed-income investments were $2.9 billion and total debt was $5.6 billion.

Housing and Infrastructure Products Segment

(Unless otherwise noted the financial numbers below exclude the effects of the Identified Items)

For the fourth quarter of 2025, Housing and Infrastructure Products income from operations of $82 million decreased by $47 million as compared to the fourth quarter of 2024. The year-over-year decrease was the result of lower sales volume, particularly for global compounds, and lower margins.

Sequentially, Housing and Infrastructure Products income from operations decreased by $69 million as compared to the third quarter of 2025. This decrease in income from operations versus the prior quarter was primarily driven by lower sales volume as a result of the typical seasonality of customer demand.

For the full year of 2025, Housing and Infrastructure Products net sales of $4.1 billion decreased by $0.2 billion as compared to 2024. Housing Products net sales of $3.5 billion decreased by $0.1 billion due to lower sales volume, particularly for roofing. Infrastructure Products net sales of $635 million decreased from $673 million in 2024 primarily due to lower average sales price at pipe and fitting and lower sales volume at global compounds. Housing and Infrastructure Products income from operations of $603 million decreased by $204 million as compared to the full year of 2024 primarily due to lower sales volume, particularly in global compounds, and lower average sales price and margins, particularly in pipe and fittings.

iv

Performance and Essential Materials Segment

(Unless otherwise noted the financial numbers below exclude the effects of the Identified Items)

For the fourth quarter of 2025, Performance and Essential Materials loss from operations was $222 million as compared to the fourth quarter of 2024's loss from operations of $41 million due to lower selling prices for most of our major products, particularly for chlorine and polyethylene, and lower sales volume, particularly for PVC resin, polyethylene and epoxy resin.

Sequentially, Performance and Essential Materials loss from operations for the fourth quarter of 2025 increased by $64 million as compared to the third quarter of 2025. This increase in loss from operations versus the prior quarter was primarily driven by lower average sales price, particularly for polyethylene, chlorine, and PVC resin.

For the full year of 2025, Performance and Essential Materials net sales of $7.0 billion decreased by $0.8 billion as compared to 2024. Performance Materials net sales of $4.0 billion in 2025 decreased by $0.6 billion primarily due to lower sales volume and average sales price for polyethylene and PVC resin and lower epoxy resin sales volume. Essential Materials net sales of $3.0 billion decreased by $0.2 billion from 2024 primarily due to lower chlorine sales volume and average sales price and lower caustic soda sales volume. Performance and Essential Materials loss from operations of $724 million decreased from 2024 due to lower average sales price and margins, lower sales volume, higher feedstock and energy costs, and a more significant impact from planned turnarounds and unplanned outages in 2025.

Forward-Looking Statements

The statements in this release and the related teleconference relating to matters that are not historical facts, including statements regarding our outlook for the performance of our business segments (such as our outlook and expected sales and earnings growth for our HIP segment), the effects of our PEM profitability improvement plan and optimization initiatives (including anticipated cost savings in 2026), the results of our acquisition of ACI, global macroeconomic conditions (including an eventual recovery in global industrial and manufacturing activity), housing demand, impacts of tariffs and duties, continuing stabilization of sales prices and volumes in both domestic and export markets for most of our products, our market position, our ability to improve safety, reliability and efficiency of our plants, further commercialization of new product innovations, our cost savings initiatives, global demand for our products, and our ability to deliver greater value to customers 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: general economic and business conditions; the cyclical nature of the industry; the availability, cost and volatility of raw materials and energy; uncertainties associated with the United States, European and worldwide economies, including those due to political tensions and conflict in the Middle East, Russia and Ukraine and elsewhere; uncertainties associated with barriers to international trade, including the imposition of tariffs and duties or trade disputes; uncertainties associated with climate change; the potential impact on demand for ethylene, polyethylene and polyvinyl chloride due to initiatives such as recycling and customers seeking alternatives to polymers; current and potential governmental regulatory actions in the United States and other countries; industry production capacity and operating rates; the supply/demand balance for Westlake's products; competitive products and pricing pressures, including from global competitors; instability in the credit and financial markets; access to capital markets; terrorist acts; operating interruptions; changes in laws and regulations, including trade policies; the effects of government shutdowns; technological developments; information systems failures and cyberattacks; foreign currency exchange risks; our ability to implement our business strategies; creditworthiness of our customers; the effect and results of litigation and settlements of litigation; and other risk factors. 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, 2024, which was filed with the SEC in February 2025, and Quarterly Report on Form 10-Q for the quarter ended September 30, 2025, which was filed with the SEC in October 2025.

v

Use of Non-GAAP Financial Measures

This release makes reference to certain "non-GAAP" financial measures, such as EBITDA, free cash flow and other measures that exclude the effects of the Identified Items, as defined in Regulation G of the U.S. Securities Exchange Act of 1934, as amended. For this purpose, a non-GAAP financial measure is generally defined by the Securities and Exchange Commission ("SEC") as a numerical measure of a registrant's historical or future financial performance, financial position or cash flows that (1) excludes amounts, or is subject to adjustments that have the effect of excluding amounts, that are included in the most directly comparable measure calculated and presented in accordance with GAAP in the statement of income, balance sheet or statement of cash flows (or equivalent statements) of the registrant; or (2) includes amounts, or is subject to adjustments that have the effect of including amounts, that are excluded from the most directly comparable measure so calculated and presented. We report our financial results in accordance with U.S. generally accepted accounting principles ("U.S. GAAP"), but believe that certain non-GAAP financial measures, such as EBITDA, free cash flow and measures that exclude the effects of the Identified Items, provide useful supplemental information to investors regarding the underlying business trends and performance of the Company's ongoing operations and are useful for period-over-period comparisons of such operations. These non-GAAP financial measures should be considered as a supplement to, and not as a substitute for, or superior to, the financial measures prepared in accordance with U.S. GAAP. A reconciliation of (i) EBITDA to net income, income from operations and net cash provided by operating activities, (ii) free cash flow to net cash provided by operating activities, and (iii) other measures reflecting adjustments for the effects of the Identified Items can be found in the financial schedules at the end of this press release.

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, Europe and North America, we provide the building blocks for vital solutions — from housing and construction, to packaging and healthcare, to automotive and consumer. For more information, visit the Company's web site at www.westlake.com.

Westlake Corporation Conference Call Information:

A conference call to discuss Westlake Corporation's fourth quarter and full year 2025 results will be held Tuesday, February 24, 2026 at 11:00 AM Eastern Time (10:00 AM Central Time). To access the conference call, it is necessary to pre-register at https://register-conf.media-server.com/register/BI0ebecf9ae9804486aff77f70a8cc367f. Once registered, you will receive a phone number and unique PIN number.

A replay of the conference call will be available beginning two hours after its conclusion. The conference call and replay will be available via webcast at https://edge.media-server.com/mmc/p/fbrmocfm.

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WESTLAKE CORPORATION

CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited)

Three Months Ended December 31, Twelve Months Ended December 31,
2025 2024 2025 2024
(In millions of dollars, except per share data and share amounts)
Net sales $ 2,533 $ 2,843 $ 11,170 $ 12,142
Cost of sales 2,446 2,515 10,357 10,185
Gross profit 87 328 813 1,957
Selling, general and administrative expenses 224 226 900 874
Impairment of goodwill 727
Amortization of intangibles 33 28 124 117
Restructuring, transaction and integration-related costs 501 8 640 91
Income (loss) from operations (671) 66 (1,578) 875
Interest expense (51) (39) (171) (159)
Other income, net 59 69 152 222
Income (loss) before income taxes (663) 96 (1,597) 938
Income tax provision (benefit) (130) 77 (126) 291
Net income (loss) (533) 19 (1,471) 647
Net income attributable to noncontrolling interests 11 12 37 45
Net income (loss) attributable to Westlake Corporation $ (544) $ 7 $ (1,508) $ 602
Earnings (loss) per common share attributable to Westlake Corporation:
Basic $ (4.22) $ 0.06 $ (11.70) $ 4.66
Diluted $ (4.22) $ 0.06 $ (11.70) $ 4.64
Weighted average common shares outstanding:
Basic 128,243,655 128,564,101 128,260,331 128,535,226
Diluted 128,243,655 129,115,674 128,260,331 129,206,922

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WESTLAKE CORPORATION

CONDENSED CONSOLIDATED BALANCE SHEETS

(Unaudited)

December 31,
2025 2024
(In millions of dollars)
ASSETS
Current assets
Cash and cash equivalents $ 2,724 $ 2,919
Available-for-sale securities 204
Accounts receivable, net 1,504 1,483
Inventories 1,653 1,697
Prepaid expenses and other current assets 131 115
Total current assets 6,216 6,214
Property, plant and equipment, net 8,605 8,633
Other assets, net 5,140 5,903
Total assets $ 19,961 $ 20,750
LIABILITIES AND EQUITY
Current liabilities (accounts payable and accrued and other liabilities) $ 2,273 $ 2,213
Current portion of long-term debt, net 497 6
Long-term debt, net 5,087 4,556
Other liabilities 2,809 2,932
Total liabilities 10,666 9,707
Total Westlake Corporation stockholders' equity 8,792 10,527
Noncontrolling interests 503 516
Total equity 9,295 11,043
Total liabilities and equity $ 19,961 $ 20,750

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WESTLAKE CORPORATION

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

Twelve Months Ended December 31,
2025 2024
(In millions of dollars)
Cash flows from operating activities
Net income (loss) $ (1,471) $ 647
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization 1,178 1,114
Impairment of goodwill 727
Deferred income taxes (177) (35)
Net loss on disposition and others 393 57
Other balance sheet changes (185) (469)
Net cash provided by operating activities 465 1,314
Cash flows from investing activities
Additions to investments in unconsolidated subsidiaries (33) (26)
Additions to property, plant and equipment (995) (1,008)
Proceeds from maturities and paydown of available-for-sale securities 68
Purchase of available-for-sale securities (272)
Other, net 9 33
Net cash used for investing activities (1,223) (1,001)
Cash flows from financing activities
Distributions to noncontrolling interests (51) (49)
Dividends paid (272) (264)
Proceeds from senior notes issuance, net 1,187
Repurchase and redemption of senior notes (254) (300)
Repurchase of common stock for treasury (63) (60)
Other, net (17) 23
Net cash provided by (used for) financing activities 530 (650)
Effect of exchange rate changes on cash, cash equivalents and restricted cash 33 (47)
Net decrease in cash, cash equivalents and restricted cash (195) (384)
Cash, cash equivalents and restricted cash at beginning of the year 2,935 3,319
Cash, cash equivalents and restricted cash at end of the year $ 2,740 $ 2,935

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WESTLAKE CORPORATION

SEGMENT INFORMATION

(Unaudited)

Three Months Ended December 31, Twelve Months Ended December 31,
2025 2024 2025 2024
(In millions of dollars)
Net external sales
Housing and Infrastructure Products
Housing Products $ 767 $ 818 $ 3,513 $ 3,644
Infrastructure Products 134 163 635 673
Total Housing and Infrastructure Products 901 981 4,148 4,317
Performance and Essential Materials
Performance Materials 930 1,121 4,018 4,626
Essential Materials 702 741 3,004 3,199
Total Performance and Essential Materials 1,632 1,862 7,022 7,825
Total reportable segments and consolidated $ 2,533 $ 2,843 $ 11,170 $ 12,142
Income (loss) from operations
Housing and Infrastructure Products $ 66 $ 129 $ 587 $ 807
Performance and Essential Materials (717) (41) (2,100) 129
Total reportable segments (651) 88 (1,513) 936
Corporate and other (20) (22) (65) (61)
Consolidated $ (671) $ 66 $ (1,578) $ 875
Depreciation and amortization
Housing and Infrastructure Products $ 61 $ 56 $ 231 $ 213
Performance and Essential Materials 233 223 934 892
Total reportable segments 294 279 1,165 1,105
Corporate and other 3 2 13 9
Consolidated $ 297 $ 281 $ 1,178 $ 1,114
Other income, net
Housing and Infrastructure Products $ 3 $ 3 $ 5 $ 30
Performance and Essential Materials 34 38 57 65
Total reportable segments 37 41 62 95
Corporate and other 22 28 90 127
Consolidated $ 59 $ 69 $ 152 $ 222

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WESTLAKE CORPORATION

RECONCILIATION OF EBITDA TO NET INCOME (LOSS) AND INCOME (LOSS) FROM OPERATIONS AND

NET CASH PROVIDED BY OPERATING ACTIVITIES (INCLUDING AND EXCLUDING IDENTIFIED ITEMS)

(Unaudited)

Three Months Ended September 30, Three Months Ended December 31, Twelve Months Ended December 31,
2025 2025 2024 2025 2024
(In millions of dollars, except percentages)
Net cash provided by operating activities $ 182 $ 225 $ 434 $ 465 $ 1,314
Changes in operating assets and liabilities and other (895) (975) (392) (2,113) (702)
Deferred income taxes (59) 217 (23) 177 35
Net income (loss) (772) (533) 19 (1,471) 647
Add:
Identified Items 744 511 1,392 75
Net income (loss) excl. Identified Items $ (28) $ (22) $ 19 $ (79) $ 722
Net income (loss) $ (772) $ (533) $ 19 $ (1,471) $ 647
Less:
Other income, net 32 59 69 152 222
Interest expense (41) (51) (39) (171) (159)
Income tax provision (benefit) 3 130 (77) 126 (291)
Income (loss) from operations (766) (671) 66 (1,578) 875
Add:
Identified Items 744 511 1,392 75
Income (loss) from operations excl. Identified Items (22) (160) 66 (186) 950
Add:
Depreciation and amortization 303 297 281 1,178 1,114
Other income, net 32 59 69 152 222
EBITDA excl. Identified Items 313 196 416 1,144 2,286
Less:
Identified Items 744 511 1,392 75
EBITDA $ (431) $ (315) $ 416 $ (248) $ 2,211
Net external sales $ 2,838 $ 2,533 $ 2,843 $ 11,170 $ 12,142
Operating income (loss) margin (27)% (26)% 2% (14)% 7%
Operating income (loss) margin excl. Identified Items (1)% (6)% 2% (2)% 8%
EBITDA margin (15)% (12)% 15% (2)% 18%
EBITDA margin excl. Identified Items 11% 8% 15% 10% 19%

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WESTLAKE CORPORATION

RECONCILIATION OF DILUTED EARNINGS (LOSS) PER COMMON SHARE TO DILUTED EARNINGS (LOSS) PER COMMON SHARE EXCLUDING IDENTIFIED ITEMS

(Unaudited)

Three Months Ended September 30, Three Months Ended December 31, Twelve Months Ended December 31,
2025 2025 2024 2025 2024
(per share data)
Diluted earnings (loss) per common share attributable to Westlake Corporation $ (6.06) $ (4.22) $ 0.06 $ (11.70) $ 4.64
Add:
Loss per common share relating to Identified Items 5.77 3.97 10.80 0.58
Diluted earnings (loss) per common share attributable to Westlake Corporation excl. Identified Items $ (0.29) $ (0.25) $ 0.06 $ (0.90) $ 5.22

WESTLAKE CORPORATION

RECONCILIATION OF FREE CASH FLOW TO NET CASH PROVIDED BY OPERATING ACTIVITIES

(Unaudited)

Three Months Ended September 30, Three Months Ended December 31, Twelve Months Ended December 31,
2025 2025 2024 2025 2024
(In millions of dollars)
Net cash provided by operating activities $ 182 $ 225 $ 434 $ 465 $ 1,314
Less:
Additions to property, plant and equipment 239 241 285 995 1,008
Free Cash Flow $ (57) $ (16) $ 149 $ (530) $ 306

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WESTLAKE CORPORATION

RECONCILIATION OF HIP SEGMENT EBITDA TO INCOME FROM OPERATIONS (INCLUDING AND EXCLUDING IDENTIFIED ITEMS)

(Unaudited)

Three Months Ended September 30, Three Months Ended December 31, Twelve Months Ended December 31,
2025 2025 2024 2025 2024
(In millions of dollars, except percentages)
Housing and Infrastructure Products Segment
Income from operations $ 151 $ 66 $ 129 $ 587 $ 807
Add:
Identified Items 16 16
Income from operations excl. Identified Items 151 82 129 603 807
Add:
Depreciation and amortization 62 61 56 231 213
Other income, net 2 3 3 5 30
EBITDA excl. Identified Items 215 146 188 839 1,050
Less:
Identified Items 16 16
EBITDA $ 215 $ 130 $ 188 $ 823 $ 1,050
Net external sales $ 1,091 $ 901 $ 981 $ 4,148 $ 4,317
Operating income margin 14% 7% 13% 14% 19%
Operating income margin excl. Identified Items 14% 9% 13% 15% 19%
EBITDA margin 20% 14% 19% 20% 24%
EBITDA margin excl. Identified Items 20% 16% 19% 20% 24%

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WESTLAKE CORPORATION

RECONCILIATION OF PEM SEGMENT EBITDA TO INCOME (LOSS) FROM OPERATIONS (INCLUDING AND EXCLUDING IDENTIFIED ITEMS)

(Unaudited)

Three Months Ended September 30, Three Months Ended December 31, Twelve Months Ended December 31,
2025 2025 2024 2025 2024
(In millions of dollars, except percentages)
Performance and Essential Materials Segment
Income (loss) from operations $ (902) $ (717) $ (41) $ (2,100) $ 129
Add:
Identified Items 744 495 1,376 75
Income (loss) from operations excl. Identified Items (158) (222) (41) (724) 204
Add:
Depreciation and amortization 238 233 223 934 892
Other income, net 10 34 38 57 65
EBITDA excl. Identified Items 90 45 220 267 1,161
Less:
Identified Items 744 495 1,376 75
EBITDA $ (654) $ (450) $ 220 $ (1,109) $ 1,086
Net external sales $ 1,747 $ 1,632 $ 1,862 $ 7,022 $ 7,825
Operating income (loss) margin (52)% (44)% (2)% (30)% 2%
Operating income (loss) margin excl. Identified Items (9)% (14)% (2)% (10)% 3%
EBITDA margin (37)% (28)% 12% (16)% 14%
EBITDA margin excl. Identified Items 5% 3% 12% 4% 15%

WESTLAKE CORPORATION

SUPPLEMENTAL INFORMATION

Product Sales Price and Volume Variance by Operating Segments

Fourth Quarter 2025 vs. Fourth Quarter 2024 Fourth Quarter 2025 vs. Third Quarter 2025
Average<br>Sales Price Volume Average<br>Sales Price Volume
Housing and Infrastructure Products % -8 % -1 % -17 %
Performance and Essential Materials -5 % -7 % -5 % -2 %
Company -4 % -7 % -3 % -7 %

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ex992_20251231wlkearning

1 Earnings Presentation 4Q and Full Year 2025


2 Fourth Quarter and Full Year 2025 Highlights Profitability Improvement Plan expected to deliver $600M EBITDA benefit in 2026 • Actions initiated in 2025 are expected to improve EBITDA by $600 million in 2026 • HIP sales and volumes benefitted from continued strong pipe and fittings demand from growing North America infrastructure spending • PEM’s 4Q’25 EBITDA performed well due to improved operational results, a gain on pension restructuring, and several smaller discrete items • Achieved $170 million of cost savings in FY’25, including $60 million in 4Q’25, meeting raised target for FY’25 and driving momentum into 2026 • Investment-grade credit rating with $2.9 billion of cash and securities $2.5B Net Sales 11% decrease QoQ $196M EBITDA(1,2) 37% decrease QoQ (2) $225M Net Cash Provided by Operating Activities (1) Reconciliation of EBITDA excl. Identified Item to Net Income, Income from Operations and Net Cash Provided by Operating Activities can be found on page 12 (2) Excludes “Identified Items” consisting of $495 million of PEM shutdown expenses and $16 million for HIP restructuring expenses in 4Q’25 and FY’25, a $727 million charge for the write-off of all the goodwill associated with the North American Chlorovinyls reporting unit and $139 million of accrued expenses and $15 million inventory write-off related to previously-announced facility shutdowns in FY’25, and $75 million of accrued expenses in FY’24 related to previously-announced facility shutdowns. $11.2B Net Sales 8% decrease YoY $1.1B EBITDA(1,2) 50% decrease YoY (2) $465M Net Cash Provided by Operating Activities 4Q 2025 Financial Results FY 2025 Financial Results


3 Westlake Corporation 4Q and FY 2025 (1) FY’25 EBITDA impacted by an elevated level of planned turnarounds and unplanned outages that are not expected to recur in FY’26 Exceeded our FY’25 cost reduction target by achieving $170 million of cost savings, including $60 million in 4Q’25 Westlake 4Q 2025 vs. 3Q 2025 Average Sales Price -3.3% Volume -7.5% Westlake 4Q 2025 vs. 4Q 2024 Average Sales Price -3.6% Volume -7.3% (1) Excludes “Identified Items” consisting of $495 million of PEM shutdown expenses and $16 million for HIP restructuring expenses in 4Q’25 and FY’25, a $727 million charge for the write-off of all the goodwill associated with the North American Chlorovinyls reporting unit in 3Q’25 and FY’25, $139 million of accrued expenses and $15 million inventory write-off related to previously-announced facility shutdowns in FY’25, and $75 million of accrued expenses in FY’24 related to previously-announced facility shutdowns. (2) Reconciliations of EBITDA excl. Identified Items, Performance and Essential Materials EBITDA excl. Identified Items, Housing and Infrastructure Products EBITDA excl. Identified Items and Corporate EBITDA to the applicable GAAP measures can be found on pages 12 and 13 4Q'25 3Q'25 QoQ% 4Q'24 YoY% FY'25 FY'24 YoY% $2,533 $2,838 (11%) $2,843 (11%) $11,170 $12,142 (8%) ($160) ($22) N.M. $66 (342%) ($186) $950 (120%) Housing and Infrastructure Products $146 $215 (32%) $188 (22%) $839 $1,050 (20%) Performance and Essential Materials $45 $90 (50%) $220 (80%) $267 $1,161 (77%) Corporate $5 $8 - $8 - $38 $75 - $196 $313 (37%) $416 (53%) $1,144 $2,286 (50%) ($ in millions) Sales Operating Income (Loss)(1) EBITDA(1,2) Lower average sales price, as the result of global overcapacity in certain PEM materials, drove lower EBITDA and margins both QoQ and YoY


4 Three Pillar Profitability Improvement Plan Profitability Improvement Plan Expected To Drive ~$600MM Per Year of EBITDA Self Help Footprint Optimization: The 2025 shutdown of unprofitable European Epoxy, North American Chlorovinyls, and Styrene facilities is expected to drive a $200MM EBITDA improvement in 2026 Cost Savings: Following the achievement of $170MM of cost savings in 2025, we continue to expect to achieve an additional $200MM of structural cost savings in 2026 ~$200MM Improved Plant Reliability: Fewer planned turnarounds and unplanned outages are expected to drive a $200MM year-over-year improvement in EBITDA in 2026 Footprint Optimization Cost Savings Improved Plant Reliability 4 ~$200MM ~$200MM


5 Housing and Infrastructure Products (“HIP”) Segment Performance(1) HIP Segment 4Q 2025 vs. 3Q 2025 Average Sales Price -0.6% Volume -16.9% HIP Segment 4Q 2025 vs. 4Q 2024 Average Sales Price -0.2% Volume -8.0% Slower North American residential construction demand drove the 8% YoY decline in sales and volume in 4Q’25 FY’25 EBITDA of $839 million met guidance and was driven by continued strong demand for pipe & fittings The breadth of HIP’s product offerings and its broad geographic reach are expected to drive FY’26 sales to $4.4 - $4.6 billion with an expected EBITDA margin of 19% - 21% (1) Excludes “Identified Items” consisting of $13 million accrued footprint optimization expenses and a $3 million loss on the sale of a compounding business in 4Q’25 and FY’25 (2) Reconciliations of HIP EBITDA excl. Identified Items to the applicable GAAP measure can be found on page 13 (3) HIP EBITDA margin is calculated by dividing HIP EBITDA excl. Identified Items by Total HIP Sales 4Q’25 and FY’25 EBITDA margin impacted by unfavorable sales mix shift and competitive market pressures in pipe & fittings 4Q'25 3Q'25 QoQ% 4Q'24 YoY% FY'25 FY'24 YoY% Housing Products Sales $767 $928 (17%) $818 (6%) $3,513 $3,644 (4%) Infrastructure Products Sales $134 $163 (18%) $163 (18%) $635 $673 (6%) Total HIP Sales $901 $1,091 (17%) $981 (8%) $4,148 $4,317 (4%) Operating Income(1) $82 $151 (46%) $129 (36%) $603 $807 (25%) EBITDA(1,2) $146 $215 (32%) $188 (22%) $839 $1,050 (20%) EBITDA Margin (1,3) 16% 20% - 19% - 20% 24% - ($ in millions)


6 Housing and Infrastructure Products Update 2 Expecting a return to sales growth in 2026, inline with HIP’s 5% - 7% long-term sales growth target, driven by benefits from product innovations and the ACI acquisition in 1Q’26 3 New PVCO pipe plant under construction to support the strong growth and market adoption for this innovative product that streamlines the installation process reducing labor costs with a sustainable footprint 4 Strong presence in repair & remodel provides stability and steady growth driven by large number of homes in prime remodel age, healthy home equity levels, and significant backlog of projects 1 Longer-term housing fundamentals remain strong due to decade-plus of under-building, increasingly favorable demographics and popularity of remote work


7 PEM Segment 4Q 2025 vs. 3Q 2025 Average Sales Price -4.9% Volume -1.6% PEM Segment 4Q 2025 vs. 4Q 2024 Average Sales Price -5.4% Volume -6.9% Lower average sales price, both QoQ and YoY, driven by lower prices for PVC resin and polyethylene, partially offset by higher prices for caustic soda Higher YoY feedstock and energy costs contributed to the EBITDA margin decline in 4Q’25 and FY’25 (1) Excludes “Identified Items” consisting of $495 million of PEM shutdown expenses in 4Q’25 and FY’25, a $727 million charge for the write-off of all the goodwill associated with the North American Chlorovinyls reporting unit in 3Q’25 and FY’25, $139 million of accrued expenses and $15 million inventory write-off related to previously-announced facility shutdowns in FY’25, and $75 million of accrued expenses in FY’24 related to previously-announced facility shutdowns. (2) Reconciliations of PEM EBITDA excl. Identified Items to the applicable GAAP measure can be found on page 13 (3) PEM EBITDA margin is calculated by dividing PEM EBITDA excl. Identified Items by Total PEM Sales Performance and Essential Materials (“PEM”) Segment Performance(1) Actions initiated in 2025, including the shutdown of European Epoxy, North American Chlorovinyls, and Styrene facilities, are expected to contribute $600 million of company- wide EBITDA improvement in 2026 4Q'25 3Q'25 QoQ% 4Q'24 YoY% FY'25 FY'24 YoY% Performance Materials Sales $930 $1,010 (8%) $1,121 (17%) $4,018 $4,626 (13%) Essential Materials Sales $702 $737 (5%) $741 (5%) $3,004 $3,199 (6%) Total PEM Sales $1,632 $1,747 (7%) $1,862 (12%) $7,022 $7,825 (10%) Operating Income (Loss)(1) ($222) ($158) N.M. ($41) N.M. ($724) $204 (455%) EBITDA(1,2) $45 $90 (50%) $220 (80%) $267 $1,161 (77%) EBITDA Margin (1,3) 3% 5% - 12% - 4% 15% - ($ in millions)


8 Performance and Essential Materials Update 2 Continued energy and feedstock advantages in North America (~85% of our production capacity) and our high degree of vertical integration relative to the global industry supports our ability to profitably run our plants at higher operating rates 3 Relatively stable North American demand as global macroeconomic conditions remain sluggish in Europe and Asia, but Westlake’s high degree of product integration and large offtake of PVC resin to the HIP segment provide less exposure to weaker economies outside North America 4 The vast majority of the targeted $600 million company-wide EBITDA contribution in 2026 from our three pillar profitability improvement plan is expected to benefit the PEM segment 1 Following global pricing declines, early 2026 has seen an increase in demand, and our pricing initiatives have ensured continued reliable supply for customers


Financial Reconciliations


10 Consolidated Statements of Operations Housing and Infrastructure Products Sales $ 901 $ 981 $ 1,091 $ 4,148 $ 4,317 Performance and Essential Materials Sales 1,632 1,862 1,747 7,022 7,825 Net sales 2,533 2,843 2,838 11,170 12,142 Cost of sales Gross profit Selling, general and administrative expenses Amortization of intangibles Impairment of goodwill Restructuring, transaction and integration-related costs Income (loss) from operations Interest expense Other income, net Income (loss) before income taxes Provision for (benefit from) income taxes Net income (loss) Net income attributable to noncontrolling interests Net income (loss) attributable to Westlake Corporation $ (544) $ 7 $ (782) $ (1,508) $ 602 Earnings (loss) per common share attributable to Westlake Corporation: Basic $ (4.22) $ 0.06 $ (6.06) $ (11.70) $ 4.66 Diluted $ (4.22) $ 0.06 $ (6.06) $ (11.70) $ 4.64 12 37 45 10 11 (772) 77 (126) 291 17 (766) (41) 32 2024 2025 2024 (In millions of dollars, except per share data) (775) (3) (130) (51) (39) (171) (159) 19 (1,471) 647 (663) 96 (1,597) 938 59 69 152 222 (533) 501 8 640 91 (671) 66 (1,578) 875 33 28 727 124 117 - - 727 - 30 224 226 900 874 228 Three months ended December 31, Twelve months ended December 31, Three months ended September 30, 87 328 813 1,957 2025 2,602 236 2,446 2,515 10,357 10,185 2025


11 Reconciliation of Net Income (Loss) Attributable to Westlake Corporation and Earnings (Loss) Per Diluted Share to Net Income (Loss) and Diluted Earnings (Loss) Per Share excl. Identified Items Net income (loss) $ (533) $ 19 $ (772) $ (1,471) $ 647 Less: Net income attributable to noncontrolling interests Net income (loss) attributable to Westlake Corporation (544) 7 (782) (1,508) 602 Add: Identified Items, after-tax Net income (loss) attributable to Westlake Corporation excl. Identified Items $ (33) $ 7 $ (38) $ (116) $ 677 Diluted earnings (loss) per common share attributable to Westlake Corporation $ (4.22) $ 0.06 $ (6.06) $ (11.70) $ 4.64 Add: Identified Items per share Diluted earnings (loss) per common share attributable to Westlake Corporation excl. Identified Items $ (0.25) $ 0.06 $ (0.29) $ (0.90) $ 5.22 511 5.77 75 - 0.58 1,392 744 - 3.97 10.80 11 12 10 37 45 (In millions of dollars, except per share data) Three months ended December 31, Three months ended September 30, Twelve months ended December 31, 2025 2024 2025 2025 2024


12 Reconciliation of EBITDA excl. Identified Items to EBITDA, Net Income (Loss), Income (Loss) from Operations and Net Cash Provided by Operating Activities Net cash provided by operating activities $ 225 $ 434 $ 182 $ 465 $ 1,314 Changes in operating assets and liabilities and other Deferred income taxes Net income (loss) Less: Other income, net Interest expense Provision for (benefit from) income taxes Income (loss) from operations Add: Depreciation and amortization Other income, net EBITDA $ (315) $ 416 $ (431) $ (248) $ 2,211 Add: Identified Items EBITDA excl. Identified Items $ 196 $ 416 $ 313 $ 1,144 $ 2,286 Income (loss) from operations margin (26%) 2% (27%) (14%) 7% EBITDA excl. Identified Items margin 8% 15% 11% 10% 19% 511 - 744 1,392 75 Three months ended December 31, Twelve months ended December 31, 20252025 2024 2025 2024 Three months ended September 30, (In millions of dollars) 35 (895)(975) (392) (2,113) (702) (59)217 (23) 177 (772)(533) 19 (1,471) 647 (41)(51) (39) (171) (159) 32 59 69 152 222 (766) (671) 66 (1,578) 875 3 130 (77) 126 (291) 303 297 281 1,178 1,114 32 59 69 152 222


13 Reconciliation of HIP EBITDA, PEM EBITDA excl. Identified Items and Corporate EBITDA to Operating Income (Loss) Three months ended December 31, Three months ended September 30, Twelve months ended December 31, 2025 2024 2025 2025 2024 Housing and Infrastructure Products EBITDA excl. Identified Items $ 146 $ 188 $ 215 $ 839 $ 1,050 Less: Identified Items 16 - - 16 - Depreciation and Amortization 61 56 62 231 213 Other income, net 3 3 2 5 30 Housing and Infrastructure Products Operating Income 66 129 151 587 807 Performance and Essential Materials EBITDA excl. Identified Items 45 220 90 267 1,161 Less: Identified Items 495 - 744 1,376 75 Depreciation and Amortization 233 223 238 934 892 Other income, net 34 38 10 57 65 Performance and Essential Materials Operating Income (Loss) (717) (41) (902) (2,100) 129 Corporate EBITDA 5 8 8 38 75 Less: Depreciation and Amortization 3 2 3 13 9 Other income, net 22 28 20 90 127 Corporate Operating Income (Loss) (20) (22) (15) (65) (61) Housing and Infrastructure Products Operating Income 66 129 151 587 807 Performance and Essential Materials Operating Income (Loss) (717) (41) (902) (2,100) 129 Corporate Operating Income (Loss) (20) (22) (15) (65) (61) Total Operating Income (Loss) (671)$ 66$ (766)$ (1,578)$ 875$  (In millions of dollars)


14 Reconciliation of Free Cash Flow to Net Cash Provided by Operating Activities Net cash provided by operating activities $ 225 $ 434 $ 182 $ 465 $ 1,314 Less: Additions to property, plant and equipment Free Cash Flow $ (16) $ 149 $ (57) $ (530) $ 306 241 285 239 995 1,008 (In millions of dollars) Three months ended December 31, Three months ended September 30, Twelve months ended December 31, 2025 2024 2025 2025 2024


15 Safe Harbor Language This presentation contains certain forward-looking statements including statements regarding our cost savings objectives and our ability to maintain synergies, pricing and demand for our products and across the industrial and manufacturing sectors, global macroeconomic conditions, anticipated sales volumes, industry outlook for both of our segments, our ability to execute our integrated strategy the operational reliability of our plants and our ability to address plant operating issues, our future operating rates and improvement of PEM operating rate in 2026, projected benefits from the shutdown of certain of our PEM facilities, projected benefits of the improved reliability of our PEM plants, our cost control and efficiency efforts, our ability to achieve our projected cost savings (such as achieving a $600 million contribution to EBITDA in 2026 from our profitability improvement plan), our future operating results, including our ability to improve revenues and EBITDA and EBITDA margin, our competitive position, the effects of changing demographics in the markets that we serve, anticipated residential construction, repair and remodel activities and infrastructure growth, long-term housing market fundamentals, changes in sales mix of our products, expectations regarding homebuilder confidence, our relationships with our customers, and our energy and feedstock cost advantages in the North American chemicals market. Actual results may differ materially depending on factors, including, but not limited to, the following: general economic and business conditions; the cyclical nature of the chemical and building products industries; the availability, cost and volatility of raw materials and energy; uncertainties associated with the United States, European and worldwide economies, including those due to political tensions and conflict in the Middle East, Russia, Ukraine and elsewhere; uncertainties associated with climate change; the potential impact on the demand for ethylene, polyethylene and polyvinyl chloride due to initiatives such as recycling and customers seeking alternatives to polymers; current and potential governmental regulatory actions in the United States and other countries; industry production capacity and operating rates; the supply/demand balance for our products; competitive products and pricing pressures; instability in the credit and financial markets; access to capital markets; terrorist acts; operating interruptions; changes in laws or regulations, including trade policies; the effects of government shutdowns; technological developments; information systems failures and cyber attacks; foreign currency exchange risks; our ability to implement our business strategies; creditworthiness of our customers; the effect and results of litigation and settlements of litigation and other factors described in our reports filed with the Securities and Exchange Commission. Many of these factors are beyond our ability to control or predict. Any of these factors, or a combination of these factors, could materially affect our future results of operations and the ultimate accuracy of the forward-looking statements. These forward-looking statements are not guarantees of our future performance, and our actual results and future developments may differ materially from those projected in the forward-looking statements. Management cautions against putting undue reliance on forward-looking statements. Every forward-looking statement speaks only as of the date of the particular statement, and we undertake no obligation to publicly update or revise any forward-looking statements. Investor Relations Contacts Steve Bender Executive Vice President & Chief Financial Officer Jeff Holy Vice President & Chief Accounting Officer Westlake Corporation 2801 Post Oak Boulevard, Suite 600, Houston, Texas 77056 | 713-960-9111