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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-Q


☒	QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
	For the quarterly period ended	September 30, 2025


☐			TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
			For the Transition Period from to

Commission File No. 001-36567

Westlake Chemical Partners LP

(Exact name of registrant as specified in its charter)


Delaware						32-0436529
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification No.)

2801 Post Oak Boulevard, Suite 600

Houston, Texas 77056

(Address of principal executive offices, including zip code)

(713) 585-2900

(Registrant's telephone number, including area code)

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 units representing limited partnership interests	WLKP	The New York Stock Exchange

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes x No ¨

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes x No ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See definitions of "large accelerated filer", "accelerated filer", "smaller reporting company" and "emerging growth company" in Rule 12b-2 of the Exchange Act:

Large accelerated filer

Accelerated filer

Non-accelerated filer

Smaller reporting company

☐

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. ¨

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act) Yes ☐ No x

The registrant had 35,245,879 common units outstanding as of October 24, 2025.

Table of Contents

TABLE OF CONTENTS


		Page
	PART I. FINANCIAL INFORMATION
Item
1)	Financial Statements	1
2)	Management's Discussion and Analysis of Financial Condition and Results of Operations	18
3)	Quantitative and Qualitative Disclosures about Market Risk	30
4)	Controls and Procedures	30

	PART II. OTHER INFORMATION

1)	Legal Proceedings	31
1A)	Risk Factors	31
5)	Other Information	31
6)	Exhibits	32

Table of Contents

PART I. FINANCIAL INFORMATION

Item 1. Financial Statements

WESTLAKE CHEMICAL PARTNERS LP

CONSOLIDATED BALANCE SHEETS

(Unaudited)


	September 30, 2025		December 31, 2024

	(in thousands of dollars, except unit amounts)
ASSETS
Current assets
Cash and cash equivalents	$	37,936	$	58,316
Receivable under the Investment Management Agreement—Westlake Corporation ("Westlake")	13,396		134,557
Accounts receivable, net—Westlake	59,665		31,975
Accounts receivable, net—third parties	16,141		11,576
Inventories	3,078		4,058
Prepaid expenses and other current assets	641		444
Total current assets	130,857		240,926
Property, plant and equipment, net	902,813		903,588
Goodwill	5,814		5,814
Deferred charges and other assets, net	232,129		137,628
Total assets	$	1,271,613	$	1,287,956
LIABILITIES
Current liabilities
Accounts payable—Westlake	$	8,741	$	20,744
Accounts payable—third parties	14,349		17,708
Accrued and other liabilities	32,036		16,920

Total current liabilities	55,126		55,372
Long-term debt payable to Westlake	399,674		399,674
Deferred income taxes	1,518		1,546
Other liabilities	1,984		2,050
Total liabilities	458,302		458,642
Commitments and contingencies (Note 12)
EQUITY
Common unitholders—publicly and privately held (21,123,649 and 21,116,326 units issued and outstanding at September 30, 2025 and December 31, 2024, respectively)	462,093		471,328
Common unitholder—Westlake (14,122,230 and 14,122,230 units issued and outstanding at September 30, 2025 and December 31, 2024, respectively)	41,091		47,373
General partner—Westlake	(242,572)		(242,572)

Total Westlake Chemical Partners LP partners' capital	260,612		276,129
Noncontrolling interest in Westlake Chemical OpCo LP ("OpCo")	552,699		553,185
Total equity	813,311		829,314
Total liabilities and equity	$	1,271,613	$	1,287,956

The accompanying notes are an integral part of the consolidated financial statements.

Table of Contents

WESTLAKE CHEMICAL PARTNERS LP

CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited)


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024

	(in thousands of dollars, except unit amounts and per unit data)
Revenue
Net sales—Westlake	$	276,539	$	215,799	$	736,396	$	690,535
Net co-products, ethylene and other sales—third parties	32,359		61,196		107,250		155,301
Total net sales	308,898		276,995		843,646		845,836
Cost of sales	209,475		160,052		592,610		525,481
Gross profit	99,423		116,943		251,036		320,355
Selling, general and administrative expenses	7,444		7,254		21,218		21,936
Income from operations	91,979		109,689		229,818		298,419
Other income (expense)
Interest expense—Westlake	(5,947)		(6,698)		(17,391)		(19,930)
Other income, net	224		1,325		2,245		3,916
Income before income taxes	86,256		104,316		214,672		282,405
Provision for income taxes	42		216		354		633
Net income	86,214		104,100		214,318		281,772
Less: Net income attributable to noncontrolling interest in OpCo	71,561		85,964		180,159		234,376
Net income attributable to Westlake Chemical Partners LP and limited partners' interest in net income	$	14,653	$	18,136	$	34,159	$	47,396
Net income per limited partner unit attributable to Westlake Chemical Partners LP (basic and diluted)
Common units	$	0.42	$	0.51	$	0.97	$	1.35
Weighted average limited partner units outstanding (basic and diluted)
Common units—publicly and privately held	21,120,704		21,112,943		21,117,801		21,108,731
Common units—Westlake	14,122,230		14,122,230		14,122,230		14,122,230

The accompanying notes are an integral part of the consolidated financial statements.

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WESTLAKE CHEMICAL PARTNERS LP

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

(Unaudited)


		Partnership
		Common Unitholders— Publicly and Privately Held		Common Unitholder— Westlake		General Partner— Westlake		Noncontrolling Interest in OpCo		Total

	(in thousands of dollars)
Balances at December 31, 2024		$	471,328	$	47,373	$	(242,572)	$	553,185	$	829,314

Net income		2,965		1,983		—		37,361		42,309



Distribution to unitholders		(9,954)		(6,657)		—		—		(16,611)
Distribution to noncontrolling interest retained in OpCo by Westlake		—		—		—		(51,906)		(51,906)
Balances at March 31, 2025		$	464,339	$	42,699	$	(242,572)	$	538,640	$	803,106

Net income		8,724		5,834		—		71,237		85,795



Distribution to unitholders		(9,954)		(6,657)		—		—		(16,611)
Distribution to noncontrolling interest retained in OpCo by Westlake		—		—		—		(41,125)		(41,125)
Balances at June 30, 2025		$	463,109	$	41,876	$	(242,572)	$	568,752	$	831,165
Net income		8,781		5,872		—		71,561		86,214

Units issued for vested phantom units		161		—		—		—		161

Distribution to unitholders		(9,958)		(6,657)		—		—		(16,615)
Distribution to noncontrolling interest retained in OpCo by Westlake		—		—		—		(87,614)		(87,614)
Balances at September 30, 2025		$	462,093	$	41,091	$	(242,572)	$	552,699	$	813,311

The accompanying notes are an integral part of the consolidated financial statements.

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WESTLAKE CHEMICAL PARTNERS LP

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

(Unaudited)


		Partnership
		Common Unitholders— Publicly and Privately Held		Common Unitholder— Westlake		General Partner— Westlake		Noncontrolling Interest in OpCo		Total

	(in thousands of dollars)
Balances at December 31, 2023		$	473,513	$	48,993	$	(242,572)	$	576,316	$	856,250

Net income		8,887		5,946		—		74,813		89,646



Distribution to unitholders		(9,950)		(6,657)		—		—		(16,607)
Distribution to noncontrolling interest retained in OpCo by Westlake		—		—		—		(81,044)		(81,044)
Balances at March 31, 2024		$	472,450	$	48,282	$	(242,572)	$	570,085	$	848,245

Net income		8,644		5,783		—		73,599		88,026

Units issued for vested phantom units		55		—		—		—		55

Distribution to unitholders		(9,950)		(6,657)		—		—		(16,607)
Distribution to noncontrolling interest retained in OpCo by Westlake		—		—		—		(84,872)		(84,872)
Balances at June 30, 2024		$	471,199	$	47,408	$	(242,572)	$	558,812	$	834,847

Net income		10,867		7,269		—		85,964		104,100

Units issued for vested phantom units		183		—		—		—		183

Distribution to unitholders		(9,953)		(6,657)		—		—		(16,610)
Distribution to noncontrolling interest retained in OpCo by Westlake		—		—		—		(84,706)		(84,706)
Balances at September 30, 2024		$	472,296	$	48,020	$	(242,572)	$	560,070	$	837,814

The accompanying notes are an integral part of the consolidated financial statements.

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WESTLAKE CHEMICAL PARTNERS LP

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)


	Nine Months Ended September 30,
	2025		2024

	(in thousands of dollars)
Cash flows from operating activities
Net income	$	214,318	$	281,772
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	93,424		84,421
Loss from disposition of property, plant and equipment	2,279		2,241
Other losses (gains), net	92		(14)
Changes in operating assets and liabilities
Accounts receivable—third parties	(4,685)		(3,859)
Net accounts receivable—Westlake	(38,532)		6,933
Inventories	980		681
Prepaid expenses and other current assets	(197)		(225)
Accounts payable—third parties	(508)		(373)
Accrued and other liabilities	16,736		(1,927)
Deferred charges and other assets and others, net	(123,817)		(17,118)
Net cash provided by operating activities	160,090		352,532
Cash flows from investing activities
Additions to property, plant and equipment	(69,988)		(35,497)
Investments with Westlake under the Investment Management Agreement	—		(15,000)
Maturities of investments with Westlake under the Investment Management Agreement	120,000		—

Net cash provided by (used for) investing activities	50,012		(50,497)
Cash flows from financing activities

Proceeds from debt payable to Westlake	135,000		163,000
Repayment of debt payable to Westlake	(135,000)		(163,000)
Distributions to noncontrolling interest retained in OpCo by Westlake	(180,645)		(250,622)
Distributions to unitholders	(49,837)		(49,824)
Net cash used for financing activities	(230,482)		(300,446)
Net increase (decrease) in cash and cash equivalents	(20,380)		1,589
Cash and cash equivalents at beginning of period	58,316		58,619
Cash and cash equivalents at end of period	$	37,936	$	60,208

The accompanying notes are an integral part of the consolidated financial statements.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

1. Description of Business and Basis of Presentation

Description of Business

Westlake Chemical Partners LP (the "Partnership") is a Delaware limited partnership formed in March 2014 to operate, acquire and develop ethylene production facilities and related assets. On August 4, 2014, the Partnership completed its initial public offering (the "IPO") of 12,937,500 common units representing limited partner interests.

In connection with the IPO, the Partnership acquired a 10.6% limited partner interest in Westlake Chemical OpCo LP ("OpCo") and a 100% interest in Westlake Chemical OpCo GP LLC ("OpCo GP"), which is the general partner of OpCo. OpCo owns three ethylene production facilities and one common carrier ethylene pipeline (collectively, the "Contributed Assets"). Since the IPO, the Partnership has periodically purchased additional limited partner interest in OpCo. Most recently, on March 29, 2019, the Partnership purchased an additional 4.5% newly-issued limited partner interest in OpCo for approximately $201,445, resulting in an aggregate 22.8% limited partner interest in OpCo, effective January 1, 2019. The remaining 77.2% limited partner interest in OpCo is owned by Westlake Corporation.

Basis of Presentation

The accompanying unaudited consolidated interim financial statements were prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the "SEC") for interim periods. Accordingly, certain information and footnotes required for complete financial statements under generally accepted accounting principles in the United States ("U.S. GAAP") have not been included. These interim consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto of the Partnership included in the annual report on Form 10-K for the fiscal year ended December 31, 2024 (the "2024 Form 10-K"), filed with the SEC on March 5, 2025. These financial statements have been prepared in conformity with the accounting principles and practices as disclosed in the notes to the consolidated financial statements of the Partnership for the fiscal year ended December 31, 2024.

References to "Westlake" refer collectively to Westlake Corporation and its subsidiaries, other than the Partnership, OpCo and OpCo GP.

The Partnership holds a 22.8% limited partner interest and the entire non-economic general partner interest in OpCo. The remaining 77.2% limited partner interest in OpCo is owned directly by Westlake, which has no rights to direct the activities that most significantly impact the economic performance of OpCo. As a result of the fact that substantially all of OpCo's activities are conducted on behalf of Westlake, and the fact that OpCo exhibits disproportionality of voting rights to economic interest, OpCo was deemed to be a variable interest entity. The Partnership, through its ownership of OpCo's general partner, has the power to direct the activities that most significantly impact the economic performance of OpCo, and it also has the obligation or right to absorb losses or receive benefits from OpCo that could potentially be significant to OpCo. As such, the Partnership was determined to be OpCo's primary beneficiary and therefore consolidates OpCo's results of operations and financial position. The Partnership's operations consist exclusively of the variable interest entity's operations and, as such, no additional variable interest entity disclosures are considered necessary. Westlake's retained interest of 77.2% is recorded as noncontrolling interest in the Partnership's consolidated financial statements.

In the opinion of the Partnership's management, the accompanying unaudited consolidated interim financial statements reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Partnership's financial position as of September 30, 2025, its results of operations for the three and nine months ended September 30, 2025 and 2024 and the changes in its cash position for the nine months ended September 30, 2025 and 2024.

Results of operations and changes in cash position for the interim periods presented are not necessarily indicative of the results that will be realized for the fiscal year ending December 31, 2025 or any other interim period. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses and the disclosure of contingent assets and liabilities. Actual results could differ materially from those estimates.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

Recently Issued Accounting Pronouncements

Measurement of Credit Losses for Accounts Receivable and Contract Assets (ASU No. 2025-05)

In July 2025, the Financial Accounting Standards Board ("FASB") issued an accounting standards update to add a practical expedient in developing reasonable and supportable forecasts as part of estimating expected credit losses. All entities may elect a practical expedient that assumes the current conditions as of the balance sheet date do not change for the remaining life of the asset. The amendments in this update are effective for annual reporting periods beginning after December 15, 2025 and interim reporting periods within those annual reporting periods, with early adoption permitted. Entities should apply the new guidance prospectively. The Partnership does not expect that this accounting standard, upon adoption, will have a material impact on the Partnership's consolidated financial statements.

Disaggregation of Income Statement Expenses (ASU No. 2024-03)

In November 2024, the FASB issued an accounting standards update requiring public entities to disclose, on an annual and interim basis, detailed information about the types of expenses in relevant expense captions presented on the face of the income statement, including amounts for inventory purchases, employee compensation, depreciation and amortization of intangible assets and a qualitative description for remaining amounts not separately disaggregated. Additionally, the update requires disclosure of total selling expenses, and in annual periods, an entity's definition of selling expenses. The amendments in this update are effective for annual reporting periods beginning after December 15, 2026, and interim periods beginning after December 15, 2027 and are to be applied either prospectively or retrospectively. Early adoption is permitted. The Partnership is currently evaluating the impact of the update on the disclosures in the Partnership's consolidated financial statements.

Income Taxes (ASU No. 2023-09)

In December 2023, the FASB issued an accounting standards update requiring additional tax disclosures primarily related to the rate reconciliation and income taxes paid disclosures. The amendments in this update will be effective for annual periods beginning after December 15, 2024 and are to be applied on a prospective basis. Retrospective application is also permitted. The update is not expected to have a material impact on the disclosures in the Partnership's consolidated financial statements.

Recently Adopted Accounting Pronouncement

Segment Reporting (ASU No. 2023-07)

In November 2023, the FASB issued an accounting standards update requiring public entities to disclose on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker ("CODM") and on an annual basis, the title and position of the CODM and an explanation of how the CODM uses the reported measure(s) of segment profit or loss in assessing segment performance and deciding how to allocate resources. The update also requires that a public entity that has a single reportable segment provide all disclosures required by the update as well as all existing segment disclosures in Topic 280. The amendments in this update are effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024 and are to be applied retrospectively to all prior periods presented in the financial statements. Early adoption is permitted. The Partnership adopted this accounting standard effective for the annual 2024 financial statements and interim period financial statements thereafter, and the adoption resulted in additional segment disclosures (see Note 13).

2. Accounts Receivable—Third Parties

Accounts receivable—third parties consist of the following:


	September 30, 2025		December 31, 2024
Trade customers	$	16,442	$	11,757
Allowance for credit losses	(301)		(181)


Accounts receivable, net—third parties	$	16,141	$	11,576

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

3. Inventories

Inventories consist of the following:


	September 30, 2025		December 31, 2024
Finished products	$	2,609	$	3,748
Feedstock, additives and chemicals	469		310
Inventories	$	3,078	$	4,058

4. Property, Plant and Equipment

Depreciation expense on property, plant and equipment of $21,966 and $21,626 is included in cost of sales in the consolidated statements of operations for the three months ended September 30, 2025 and 2024, respectively. Depreciation expense on property, plant and equipment of $64,389 and $64,993 is included in cost of sales in the consolidated statements of operations for the nine months ended September 30, 2025 and 2024, respectively.

5. Deferred Charges and Other Assets

Amortization expense on deferred charges and other assets of $11,906 and $6,486 is included in cost of sales in the consolidated statements of operations for the three months ended September 30, 2025 and 2024, respectively. Amortization expense on deferred charges and other assets of $29,035 and $19,428 is included in cost of sales in the consolidated statements of operations for the nine months ended September 30, 2025 and 2024, respectively.

6. Distributions and Net Income Per Limited Partner Unit

On October 28, 2025, the board of directors of Westlake Chemical Partners GP LLC ("Westlake GP"), the Partnership's general partner, declared a quarterly cash distribution for the three months ended September 30, 2025 of 0.4714 per common unit. This distribution is payable on November 26, 2025 to unitholders of record as of November 10, 2025.

Distributions are declared subsequent to quarter end; therefore, the table below represents total cash distributions declared from earnings of the related periods pertaining to such distributions.


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Net income attributable to the Partnership	$	14,653	$	18,136	$	34,159	$	47,396
Less:
Limited partners' distribution declared on common units	16,615		16,611		49,838		49,826


Net income in excess of distribution (Distribution in excess of net income)	$	(1,962)	$	1,525	$	(15,679)	$	(2,430)

Net income per unit applicable to common limited partner units is computed by dividing the respective limited partners' interest in net income by the weighted-average number of common units outstanding for the period. Because the Partnership has more than one class of participating securities, it uses the two-class method when calculating the net income per unit applicable to limited partners. The classes of participating securities include common units and incentive distribution rights. Net income attributable to the Partnership is allocated to the unitholders in accordance with their respective ownership percentages in preparation of the consolidated statements of changes in equity. However, when distributions related to the incentive distribution rights are made, net income equal to the amount of those distributions is first allocated to the general partner before the remaining net income is allocated to the unitholders based on their respective ownership percentages. Basic and diluted net income per unit is the same because the Partnership does not have any potentially dilutive units outstanding for the periods presented.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)


	Three Months Ended September 30, 2025
	Limited Partners' Common Units		Incentive Distribution Rights		Total
Net income attributable to the Partnership:
Distribution	$	16,615	$	—	$	16,615
Distribution in excess of net income	(1,962)		—		(1,962)
Net income	$	14,653	$	—	$	14,653
Weighted average units outstanding:
Basic and diluted	35,242,934				35,242,934
Net income per limited partner unit:
Basic and diluted	$	0.42


	Three Months Ended September 30, 2024
	Limited Partners' Common Units		Incentive Distribution Rights		Total
Net income attributable to the Partnership:
Distribution	$	16,611	$	—	$	16,611
Net income in excess of distribution	1,525		—		1,525
Net income	$	18,136	$	—	$	18,136
Weighted average units outstanding:
Basic and diluted	35,235,173				35,235,173
Net income per limited partner unit:
Basic and diluted	$	0.51


	Nine Months Ended September 30, 2025
	Limited Partners' Common Units		Incentive Distribution Rights		Total
Net income attributable to the Partnership:
Distribution	$	49,838	$	—	$	49,838
Distribution in excess of net income	(15,679)		—		(15,679)
Net income	$	34,159	$	—	$	34,159
Weighted average units outstanding:
Basic and diluted	35,240,031				35,240,031
Net income per limited partner unit:
Basic and diluted	$	0.97

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)


	Nine Months Ended September 30, 2024
	Limited Partners' Common Units		Incentive Distribution Rights		Total
Net income attributable to the Partnership:
Distribution	$	49,826	$	—	$	49,826
Distribution in excess of net income	(2,430)		—		(2,430)
Net income	$	47,396	$	—	$	47,396
Weighted average units outstanding:
Basic and diluted	35,230,961				35,230,961
Net income per limited partner unit:
Basic and diluted	$	1.35

The amended Partnership Agreement provides that the Partnership will distribute cash that is deemed to be an appropriate portion of the Partnership's total operating surplus. If cash distributions to the Partnership's unitholders exceed $1.2938 per common unit in any quarter, the Partnership's unitholders and Westlake, as the holder of the Partnership's incentive distribution rights, will receive distributions according to the following percentage allocations:


	Marginal Percentage Interest in Distributions
Total Quarterly Distribution Per Unit	Unitholders		IDR Holders
Above $1.2938 up to $1.4063	85.0	%	15.0	%
Above $1.4063 up to $1.6875	75.0	%	25.0	%
Above $1.6875	50.0	%	50.0	%

The Partnership's distribution for the three months ended September 30, 2025 did not exceed the $1.2938 per unit threshold, and, as a result, no distribution was made with respect to the Partnership's incentive distribution rights to Westlake, as the holder of the Partnership's incentive distribution rights.

Distributions Per Common Unit

Distributions per common unit for the three and nine months ended September 30, 2025 and 2024 were as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Distributions per common unit	$	0.4714	$	0.4714	$	1.4142	$	1.4142

7. Partners' Equity

On October 4, 2018, the Partnership and Westlake Chemical Partners GP LLC, the general partner of the Partnership, entered into an Equity Distribution Agreement with UBS Securities LLC, Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., RBC Capital Markets, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC to offer and sell the Partnership's common units, from time to time, up to an aggregate offering amount of $50,000. The Equity Distribution Agreement was amended on February 28, 2020 to reference a new shelf registration and subsequent renewals thereof for utilization under this agreement. No common units were issued under this program as of September 30, 2025.

On March 29, 2019, the Partnership completed the issuance and sale of 2,940,818 common units at a price of $21.40 per unit through a private placement. TTWF LP, Westlake's principal stockholder and a related party, acquired 1,401,869 common units out of 2,940,818 common units issued in the private placement.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

8. Related Party Transactions

Related party transactions between the Partnership, OpCo and Westlake are primarily based on agreements such as the Ethylene Sales Agreement, the Feedstock Supply Agreement, the Services and Secondment Agreement, Site Lease Agreements, the Omnibus Agreement, the Investment Management Agreement, the Exchange Agreement, the OpCo Partnership Agreement, the OpCo Revolver and the MLP Revolver. These agreements, discussed in detail in the Partnership's 2024 consolidated financial statements included in the 2024 Form 10-K filed on March 5, 2025, reflect the pervasive effect of the relationship with Westlake on the Partnership's operations and its consolidated financial statements. Pursuant to these agreements, the Partnership and OpCo regularly enter into transactions with Westlake. See below for descriptions and details of significant related party transactions.

Sales to Related Parties

OpCo sells ethylene to Westlake under the Ethylene Sales Agreement. Additionally, the Partnership and OpCo from time to time provide other services or products for which it charges Westlake a fee.

OpCo sells a significant portion of its ethylene production to Westlake. Sales to related parties were as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Net sales—Westlake	$	276,539	$	215,799	$	736,396	$	690,535

As of September 30, 2025, OpCo forecasted an annual production deficiency under the Ethylene Sales Agreement for the full year 2025 primarily due to the Petro 1 turnaround extending into April 2025, which was later than the planned completion in March 2025. As a result, the Partnership recognized buyer deficiency fees of $13,613 in the second quarter of 2025. The total buyer deficiency fees recognized by the Partnership during the nine months ended September 30, 2025 was $13,613. The buyer deficiency fee is measured based upon the lower of the actual production deficiency at period end or the estimated annual production deficiency. The buyer deficiency fees are classified as a component of net sales—Westlake.

Cost of Sales from Related Parties

Charges for goods and services purchased by the Partnership and OpCo from Westlake and included in cost of sales relate primarily to feedstock purchased under the Feedstock Supply Agreement and services provided under the Services and Secondment Agreement.

A significant portion of the Partnership's inputs included in cost of sales are supplied by Westlake. Charges from related parties for significant inputs included in cost of sales were as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Feedstock purchased from Westlake and included in cost of sales	$	95,110	$	65,053	$	271,176	$	220,597
Other charges from Westlake and included in cost of sales	33,952		31,274		99,158		92,940

Services from Related Parties Included in Selling, General and Administrative Expenses

Charges for services purchased by the Partnership from Westlake and included in selling, general and administrative expenses primarily relate to services Westlake performs on behalf of the Partnership under the Omnibus Agreement, including the Partnership's finance, legal, information technology, human resources, communication, ethics and compliance and other administrative functions.

Charges from related parties included within selling, general and administrative expenses were as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Services received from Westlake and included in selling, general and administrative expenses	$	6,691	$	6,618	$	18,398	$	19,793

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

Goods and Services from Related Parties Capitalized as Assets

Charges for goods and services purchased by the Partnership and OpCo from Westlake, which were capitalized as assets, relate primarily to the services of Westlake employees under the Services and Secondment Agreement.

Charges from related parties for goods and services capitalized as assets were as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Goods and services purchased from Westlake and capitalized as assets	$	462	$	795	$	6,943	$	1,644

Receivable under the Investment Management Agreement

On August 1, 2017, the Partnership, OpCo and Westlake executed an investment management agreement (the "Investment Management Agreement") that authorized Westlake to invest the Partnership's and OpCo's excess cash with Westlake for durations of up to a maximum of nine months. Per the terms of the Investment Management Agreement, the Partnership earns a market return plus five basis points and Westlake provides daily availability of the invested cash to meet any liquidity needs of the Partnership or OpCo. Accrued interest of $224 and $1,385 was included in the receivable under the Investment Management Agreement balance at September 30, 2025 and December 31, 2024, respectively. Total interest earned related to the Investment Management Agreement was $224 and $1,368 for the three months ended September 30, 2025 and 2024, respectively, and $2,333 and $3,979 for the nine months ended September 30, 2025 and 2024, respectively.

The Partnership's receivable under the Investment Management Agreement was as follows:


	September 30, 2025		December 31, 2024
Receivable under the Investment Management Agreement	$	13,396	$	134,557

Accounts Receivable from Related Parties

The Partnership's accounts receivable from Westlake result primarily from ethylene sales to Westlake and any buyer deficiency fee and shortfall fee recognized under the Ethylene Sales Agreement.

The buyer deficiency fees discussed above under "Sales to Related Parties" recognized in the nine months ended September 30, 2025 are scheduled to be received by the Partnership after December 31, 2025.

As a result of the Partnership's decision to postpone the maintenance turnaround at the Petro 1 facility from the third quarter of 2024 to the first quarter of 2025, OpCo's production resulted in "excess quantities" of ethylene for the contract year ended December 31, 2024. Pursuant to the terms of the Ethylene Sales Agreement, the excess quantities produced were sold to Westlake at prices that excluded certain non-variable costs of production. As of December 31, 2024, accounts receivable included sales associated with the excess quantities, which were at a lower sales price.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

The Partnership's accounts receivable from Westlake were as follows:


	September 30, 2025		December 31, 2024
Accounts receivable—Westlake	$	59,665	$	31,975

Accounts Payable to Related Parties

The Partnership's accounts payable to Westlake result primarily from feedstock purchases under the Feedstock Supply Agreement and services provided under the Services and Secondment Agreement and the Omnibus Agreement.

The Partnership's accounts payable to Westlake were as follows:


	September 30, 2025		December 31, 2024

Accounts payable—Westlake	$	8,741	$	20,744

Related Party Leases

OpCo is obligated to Westlake under various long-term and short-term noncancelable operating leases, primarily related to rail cars and land. Operating lease rentals paid to Westlake for such leases were $468 and $471 for the three months ended September 30, 2025 and 2024, respectively, and $1,246 and $1,326 for the nine months ended September 30, 2025 and 2024 respectively, and are reflected in other charges from Westlake that are included in cost of sales.

OpCo has two site lease agreements with Westlake, each of which has a term of 50 years. Pursuant to the site lease agreements, OpCo pays Westlake one dollar per site per year.

Debt Payable to Related Parties

See Note 9 for a description of related party debt payable balances.

Interest on related party debt payable balances, net of capitalized interest, for the three months ended September 30, 2025 and 2024 was $5,947 and $6,698, respectively. Interest on related party debt payable balances, net of capitalized interest, for the nine months ended September 30, 2025 and 2024 was $17,391 and $19,930, respectively. Interest on related party debt payable is presented as interest expense—Westlake in the consolidated statements of operations. At September 30, 2025 and December 31, 2024, accrued interest on related party debt was $5,945 and $5,848, respectively, and is reflected as a component of accrued and other liabilities in the consolidated balance sheets.

Debt payable to related parties was as follows:


	September 30, 2025		December 31, 2024
Long-term debt payable to Westlake	$	399,674	$	399,674

Major Customer and Concentration of Credit Risk

During the three months ended September 30, 2025 and 2024, Westlake accounted for approximately 89.5% and 77.9%, respectively, of the Partnership's net sales. During the nine months ended September 30, 2025 and 2024, Westlake accounted for approximately 87.3% and 81.6%, respectively, of the Partnership's net sales.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

9. Long-Term Debt Payable to Westlake

Long-term debt payable to Westlake consists of the following:


	September 30, 2025		December 31, 2024
OpCo Revolver	$	22,619	$	22,619
MLP Revolver	377,055		377,055
Long-term debt payable to Westlake	$	399,674	$	399,674

As of September 30, 2025, outstanding borrowings under the OpCo Revolver and the MLP Revolver bore interest at the Secured Overnight Financing Rate, as administered by the Federal Reserve Bank of New York ("SOFR") plus the Applicable Margin plus a 0.10% credit spread adjustment. The Applicable Margin under the OpCo Revolver is 1.75%. The Applicable Margin under the MLP Revolver varies between 1.75% and 2.75%, depending on the Partnership's Consolidated Leverage Ratio. The OpCo Revolver and the MLP Revolver are scheduled to mature on July 12, 2027.

The weighted average interest rate on all long-term debt was 6.1% and 6.4% at September 30, 2025 and December 31, 2024, respectively.

As of September 30, 2025, the Partnership was in compliance with all of the covenants under the OpCo Revolver and the MLP Revolver.

10. Fair Value Measurements

The Partnership reports certain assets and liabilities at fair value, which is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). Under the accounting guidance for fair value measurements, inputs used to measure fair value are classified in one of three levels:

Level 1: Quoted market prices in active markets for identical assets or liabilities.

Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data.

Level 3: Unobservable inputs that are not corroborated by market data.

The Partnership has financial assets and liabilities subject to fair value measures. These financial assets and liabilities include cash and cash equivalents, accounts receivable, net, accounts payable and long-term debt payable to Westlake, all of which are recorded at carrying value. The amounts reported in the consolidated balance sheets for cash and cash equivalents, accounts receivable, net and accounts payable approximate their fair value due to the short maturities of these instruments. The carrying and fair values of the Partnership's long-term debt at September 30, 2025 and December 31, 2024 are summarized in the table below. The fair value of long-term debt is determined based on the present value of expected future cash flows using a discounted cash flow methodology. Because the Partnership's valuation methodology used for long-term debt requires the use of significant unobservable inputs, the inputs used to measure the fair value of the Partnership's long-term debt are classified as Level 3 within the fair value hierarchy. Inputs used to estimate the fair values of the Partnership's long-term debt include the selection of an appropriate discount rate.


	September 30, 2025				December 31, 2024
	Carrying Value		Fair Value		Carrying Value		Fair Value
Long-term debt payable to Westlake	$	399,674	$	409,299	$	399,674	$	411,489

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

11. Supplemental Information

Accrued and Other Liabilities

Accrued and other liabilities were $32,036 and $16,920 at September 30, 2025 and December 31, 2024, respectively. Accrued taxes, accrued turnaround costs and accrued interest on related party debt, which are components of accrued and other liabilities, were $6,177, $12,649 and $5,945, respectively, at September 30, 2025 and $2,415, $933 and $5,848, respectively, at December 31, 2024. No other component of accrued and other liabilities was more than five percent of total current liabilities.

Cash Flow Information

Non-cash Investing Activity

Capital expenditure related liabilities, included in accounts payable—third parties and accrued and other liabilities, were $5,768 and $7,376 at September 30, 2025 and 2024, respectively.

Interest Paid

Interest paid by the Partnership, net of interest capitalized, was $17,292 and $19,852 for the nine months ended September 30, 2025 and 2024, respectively.

Operating Leases

Right-of-use assets obtained in exchange for operating lease obligations were $920 and $758 for the nine months ended September 30, 2025 and 2024, respectively.

12. Commitments and Contingencies

The Partnership is subject to environmental laws and regulations that can impose civil and criminal sanctions and that may require the Partnership to mitigate the effects of contamination caused by the release or disposal of hazardous substances into the environment. These laws include the federal Clean Air Act, the federal Water Pollution Control Act, the Resource Conservation and Recovery Act, the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA"), the Toxic Substances Control Act and various other federal, state and local laws and regulations. Under CERCLA, an owner or operator of property may be held strictly liable for remediating contamination without regard to whether that person caused the contamination, and without regard to whether the practices that resulted in the contamination were legal at the time they occurred. Because the Partnership's production sites have a history of industrial use, it is impossible to predict precisely what effect these legal requirements will have on the Partnership. Pursuant to the Omnibus Agreement, certain subsidiaries of Westlake will indemnify the Partnership for certain environmental and other liabilities that occurred or existed prior to August 4, 2014. Pursuant to the Services and Secondment Agreement, certain subsidiaries of Westlake will indemnify the Partnership for certain liabilities incurred in connection with the performance of Westlake's services under such agreement.

The Partnership is also involved in other legal proceedings incidental to the conduct of its business. After considering all relevant facts and circumstances, including applicable insurance and indemnification by Westlake, the Partnership does not believe that any of these legal proceedings will have a material adverse effect on its financial condition, results of operations or cash flows.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

13. Segment Information

The Partnership has one operating segment, which is the Partnership's reportable segment, OpCo. Consolidated net sales and provision for income taxes as disclosed in the consolidated statements of operations and depreciation and amortization and additions to property, plant and equipment as disclosed in the consolidated statements of cash flows are fully attributed to the OpCo segment, and as such, separate OpCo segment amounts are not repeated in the tables below.


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024

Significant segment expenses and other segment items
OpCo
Raw material, energy, manufacturing and logistics costs	$	175,603	$	131,940	$	499,186	$	441,060
Depreciation and amortization	33,872		28,112		93,424		84,421
Total cost of sales	209,475		160,052		592,610		525,481
Selling, general and administrative expenses	6,579		6,372		18,653		19,018
Other segment items (1)	175		(749)		(913)		(2,168)

Interest expense—Westlake
OpCo	$	357	$	360	$	978	$	1,115
Corporate	5,590		6,338		16,413		18,815
	$	5,947	$	6,698	$	17,391	$	19,930

Net income
OpCo	$	92,669	$	111,320	$	233,296	$	303,505

A reconciliation of total segment net income to consolidated net income is as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024
Net income from OpCo	$	92,669	$	111,320	$	233,296	$	303,505
Corporate net loss	(6,455)		(7,220)		(18,978)		(21,733)
Net income	$	86,214	$	104,100	$	214,318	$	281,772


	September 30, 2025		December 31, 2024
Total assets
OpCo	$	1,237,368	$	1,238,420
Corporate	34,245		49,536
	$	1,271,613	$	1,287,956

_____________________________

(1)Other segment items includes interest expense—Westlake, other income, net and provision for income taxes.

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WESTLAKE CHEMICAL PARTNERS LP

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS—Continued

(Unaudited)

(in thousands of dollars, except unit amounts and per unit data)

14. Subsequent Events

On October 28, 2025, OpCo and Westlake agreed to renew both the Ethylene Sales Agreement and the Feedstock Supply Agreement through December 31, 2027 in accordance with their respective terms (the "Renewal"), which each provide for an initial term through December 31, 2026 and automatic 12-month renewal periods until terminated at the end of the initial term or any renewal term on not less than 12-months' notice.

In connection with the Renewal, on October 28, 2025, OpCo and certain affiliates of Westlake entered into an amendment to the Services and Secondment Agreement to align the date of expiration of such agreement with the date of expiration term of the Ethylene Sales Agreement. In addition, the Partnership, OpCo and certain affiliates of Westlake also entered into an amendment to the Omnibus Agreement to provide that the Omnibus Agreement would terminate upon termination of the Ethylene Sales Agreement. The amendment also addressed certain procedural requirements in connection with Westlake's obligation to indemnify the Partnership for certain matters, including, among others, environmental and tax matters, under the Omnibus Agreement.

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Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations

This Management's Discussion and Analysis of Financial Condition and Results of Operations section should be read in conjunction with the accompanying consolidated financial statements and the notes thereto and the consolidated financial statements and notes thereto included in Westlake Chemical Partners LP's annual report on Form 10-K for the fiscal year ended December 31, 2024 (the "2024 Form 10-K"), as filed with the SEC on March 5, 2025. Unless otherwise indicated, references in this report to "we," "our," "us" or like terms, refer to Westlake Chemical Partners LP (the "Partnership"), Westlake Chemical OpCo LP ("OpCo") and Westlake Chemical OpCo GP LLC ("OpCo GP"). References to "Westlake" refer to Westlake Corporation and its consolidated subsidiaries other than the Partnership, OpCo GP and OpCo. The following discussion contains forward-looking statements. Please read "Forward-Looking Statements" for a discussion of limitations inherent in such statements.

Partnership Overview

We are a Delaware limited partnership formed by Westlake to operate, acquire and develop ethylene production facilities and related assets. On August 4, 2014, we closed our initial public offering (the "IPO") of 12,937,500 common units. In connection with the IPO, we acquired a 10.6% interest in OpCo and a 100% interest in OpCo GP, which is the general partner of OpCo. On April 29, 2015, we purchased an additional 2.7% newly-issued limited partner interest in OpCo, resulting in an aggregate 13.3% limited partner interest in OpCo effective April 1, 2015. The 12,686,115 subordinated units of the Partnership, all of which were previously owned by Westlake, were converted into common units of the Partnership on August 30, 2017. On September 29, 2017, we completed a secondary public offering of 5,175,000 common units and purchased an additional 5.0% newly-issued limited partner interest in OpCo, resulting in an aggregate 18.3% limited partner interest in OpCo effective July 1, 2017. On March 29, 2019, we completed a private placement of 2,940,818 common units and used the net proceeds to purchase an additional 4.5% interest in OpCo, effective January 1, 2019, resulting in us owning an aggregate 22.8% limited partner interest in OpCo.

Currently, our sole revenue generating asset is our 22.8% limited partner interest in OpCo, a limited partnership formed by Westlake and us in anticipation of the IPO to own and operate an ethylene production business. We control OpCo through our ownership of its general partner. Westlake retains the remaining 77.2% limited partner interest in OpCo as well as a significant interest in us through its ownership of our general partner, 40.1% of our limited partner units (consisting of 14,122,230 common units) and our incentive distribution rights. OpCo's assets include (1) two ethylene production facilities ("Petro 1" and "Petro 2" and, collectively, "Lake Charles Olefins") at Westlake's Lake Charles, Louisiana site; (2) one ethylene production facility ("Calvert City Olefins") at Westlake's Calvert City, Kentucky site; and (3) a 200-mile common carrier ethylene pipeline (the "Longview Pipeline") that runs from Mont Belvieu, Texas to Westlake's Longview, Texas facility.

Neither we nor OpCo has any employees. OpCo and Westlake are parties to the Services and Secondment Agreement, pursuant to which Westlake provides OpCo with various utility services, comprehensive operating services for OpCo's units, services for the maintenance and operation of the common facilities and seconded employees to perform all services required under the agreement. The Services and Secondment Agreement, as amended, provides for an initial term through December 31, 2026 and, subject to the simultaneous renewal of the Ethylene Sales Agreement, automatic 12-month renewal periods until terminated at the end of the initial term or any renewal term on not less than 12-months' notice.

How We Generate Revenue

We generate revenue primarily by selling ethylene and the resulting co-products we produce. OpCo and Westlake have entered into an ethylene sales agreement (the "Ethylene Sales Agreement") pursuant to which we generate a substantial majority of our revenue. The Ethylene Sales Agreement is a long-term, fee-based agreement with a minimum purchase commitment and includes variable pricing based on OpCo's actual feedstock and natural gas costs and estimated other costs of producing ethylene (including OpCo's estimated operating costs and a five-year average of OpCo's expected future maintenance capital expenditures and other turnaround expenditures based on OpCo's planned ethylene production capacity for the year), plus a fixed margin per pound of $0.10 less revenue from co-products sales. Pursuant to the Ethylene Sales Agreement, Westlake's obligation to pay for the annual minimum commitment (95% of OpCo's budgeted ethylene production), which is measured on an annual basis, is not reduced for a force majeure event lasting fewer than 45 consecutive days. In the event of a force majeure event, we recognize buyer deficiency fees representing fixed margin and unavoided operating and maintenance capital expenditures and maintenance expenses per pound of volume committed by Westlake during the force majeure period. In the event Westlake purchases less than its annual commitment, we recognize buyer deficiency fees representing fixed margin and all expenses and expenditures incurred per pound of volume committed but not taken by Westlake. Payment for the buyer deficiency fee is scheduled to be received by the Partnership after the conclusion of the year.

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Westlake has an option to take 95% of volumes in excess of the minimum commitment on an annual basis under the Ethylene Sales Agreement if we produce more than our planned production. Under the Ethylene Sales Agreement, the price for the sale of such excess ethylene to Westlake is based on a formula similar to that used for the minimum purchase commitment, with the exception of certain fixed costs.

In addition, under the Ethylene Sales Agreement, if production costs billed to Westlake on an annual basis are less than 95% of the actual production costs incurred by OpCo during the contract year, OpCo is entitled to recover the shortfall in such production costs (proportionate to the volume sold to Westlake) in the subsequent year ("Shortfall"). The Shortfall is generally recognized during the period in which the related operating, maintenance or turnaround activities occur.

Operating Expenses, Maintenance Capital Expenditures and Turnaround Costs

Our management seeks to maximize the profitability of our operations by effectively managing operating expenses, maintenance capital expenditures and turnaround costs. Our operating expenses are comprised primarily of feedstock costs and natural gas, labor expenses (including contractor services), utility costs (other than natural gas) and turnaround and maintenance expenses. With the exception of feedstock (including natural gas) and utilities-related expenses, operating expenses generally remain relatively stable across broad ranges of production volumes but can fluctuate from period to period depending on the circumstances, particularly maintenance and turnaround activities. Our maintenance capital expenditures and turnaround costs are comprised primarily of maintenance of our ethylene production facilities and the amortization of capitalized turnaround costs. These capital expenditures relate to the maintenance and integrity of our facilities. We capitalize the costs of major maintenance activities, or turnarounds, and amortize the costs over the period until the next planned turnaround of the affected facility.

Operating expenses, maintenance capital expenditures and turnaround costs are built into the price per pound of ethylene charged to Westlake under the Ethylene Sales Agreement. Because the expenses other than feedstock costs and natural gas are based on forecasted amounts and remain a fixed component of the price per pound of ethylene sold under the Ethylene Sales Agreement for any given 12-month period, our ability to manage operating expenses, maintenance expenditures and turnaround costs may directly affect our profitability and cash flows. The impact on profitability is partially mitigated by the fact that we generally recognize any Shortfall as revenue in the period such costs and expenses are incurred. We seek to manage our operating and maintenance expenses on our ethylene production facilities by scheduling maintenance and turnarounds over time to avoid significant variability in our operating margins and minimize the impact on our cash flows, without compromising our commitment to safety and environmental stewardship. In addition, we reserve cash on an annual basis from what we would otherwise distribute to minimize the impact of turnaround costs in the year of incurrence. The purchase price under the Ethylene Sales Agreement is not designed to cover capital expenditures for expansions.

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MLP Distributable Cash Flow and EBITDA

The body of accounting principles generally accepted in the United States is commonly referred to as "GAAP." 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 use the non-GAAP measures of MLP distributable cash flow and EBITDA to analyze our performance. We define distributable cash flow as net income plus depreciation, amortization and disposition of property, plant and equipment, less contributions for turnaround reserves, maintenance capital expenditures and mark-to-market adjustment on derivative contracts. We define MLP distributable cash flow as distributable cash flow less distributable cash flow attributable to Westlake's noncontrolling interest in OpCo and distributions attributable to the incentive distribution rights holder. MLP distributable cash flow does not reflect changes in working capital balances. We define EBITDA as net income before interest expense, income taxes, depreciation and amortization. We use each of MLP distributable cash flow and EBITDA to analyze our performance. Fees for a buyer deficiency and Shortfall are included in net income in the periods in which they are recognized. MLP distributable cash flow and EBITDA are non-GAAP supplemental financial measures that management and external users of our consolidated financial statements, such as industry analysts, investors, lenders and rating agencies, may use to assess our operating performance as compared to other publicly-traded partnerships; our ability to incur and service debt and fund capital expenditures; and the viability of acquisitions and other capital expenditure projects and the returns on investment of various investment opportunities.

MLP distributable cash flow is not a substitute for the GAAP measures of net income and net cash provided by operating activities. MLP distributable cash flow has important limitations as an analytical tool because it excludes some but not all items that affect net income and net cash provided by operating activities. EBITDA is not a substitute for the GAAP measures of net income, income from operations and net cash provided by operating activities. In addition, it should be noted that companies calculate EBITDA differently and, therefore, EBITDA as presented for us may not be comparable to EBITDA reported by other companies. EBITDA has material limitations as a performance measure because it excludes interest expense, depreciation and amortization, and income taxes. Reconciliations for each of MLP distributable cash flow and EBITDA are included in the "Results of Operations" section below.

Recent Developments

Renewal of the Ethylene Sales Agreement and Feedstock Supply Agreement

Amendments to the Services and Secondment Agreement and Omnibus Agreement

In connection with the Renewal, on October 28, 2025, OpCo and certain affiliates of Westlake entered into an amendment to the Services and Secondment Agreement to align the date of expiration of such agreement with the date of expiration of the Ethylene Sales Agreement. In addition, the Partnership, OpCo and certain affiliates of Westlake also entered into an amendment to the Omnibus Agreement to provide that the Omnibus Agreement would terminate upon termination of the Ethylene Sales Agreement. The amendment also addressed certain procedural requirements in connection with Westlake's obligation to indemnify the Partnership for certain matters, including, among others, environmental and tax matters, under the Omnibus Agreement.

Please refer to the 2024 Form 10-K and Note 8 to the unaudited consolidated financial statements within this Quarterly Report on Form 10-Q for additional discussions related to these agreements.

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Results of Operations


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024

	(in thousands of dollars)
Revenue
Net sales—Westlake	$	276,539	$	215,799	$	736,396	$	690,535
Net co-products, ethylene and other sales—third parties	32,359		61,196		107,250		155,301
Total net sales	308,898		276,995		843,646		845,836
Cost of sales	209,475		160,052		592,610		525,481
Gross profit	99,423		116,943		251,036		320,355
Selling, general and administrative expenses	7,444		7,254		21,218		21,936
Income from operations	91,979		109,689		229,818		298,419
Other income (expense)
Interest expense—Westlake	(5,947)		(6,698)		(17,391)		(19,930)
Other income, net	224		1,325		2,245		3,916
Income before income taxes	86,256		104,316		214,672		282,405
Provision for income taxes	42		216		354		633
Net income	86,214		104,100		214,318		281,772
Less: Net income attributable to noncontrolling interest in OpCo	71,561		85,964		180,159		234,376
Net income attributable to Westlake Chemical Partners LP	$	14,653	$	18,136	$	34,159	$	47,396
MLP distributable cash flow (1)	$	14,886	$	17,879	$	34,607	$	51,906
EBITDA (2)	$	126,075	$	139,126	$	325,487	$	386,756
____________

(1) See "Reconciliation of MLP Distributable Cash Flow to Net Income and Net Cash Provided by Operating Activities" below.
(2) See "Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities" below.


	Three Months Ended September 30, 2025				Nine Months Ended September 30, 2025
	Average Sales Price		Volume		Average Sales Price		Volume
Net sales percentage change from prior-year period due to average sales price and volume	+12.0	%	-0.5	%	+10.1	%	-11.9	%

Three Months Ended September 30, 2025

Nine Months Ended September 30, 2025

Domestic US prices percentage change from prior-year period for fuel cost and feedstock

Fuel cost (Natural Gas)

+45.2

+60.6

Feedstock (Ethane)

+47.4

+37.6

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Reconciliation of MLP Distributable Cash Flow to Net Income and Net Cash Provided by Operating Activities

The following table presents reconciliations of MLP distributable cash flow to net income and net cash provided by operating activities, the most directly comparable GAAP financial measures, for each of the periods indicated.


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024

	(in thousands of dollars)
Net cash provided by operating activities	$	105,238	$	126,071	$	160,090	$	352,532
Loss from disposition of property, plant and equipment	(1,788)		(416)		(2,279)		(2,241)
Changes in operating assets and liabilities and other	(17,236)		(21,555)		56,507		(68,519)
Net income	86,214		104,100		214,318		281,772
Add:
Depreciation, amortization and disposition of property, plant and equipment	35,660		28,528		95,703		86,662
Less:
Contribution to turnaround reserves	(10,486)		(11,903)		(28,504)		(32,051)
Maintenance capital expenditures	(24,150)		(17,753)		(65,233)		(34,808)
Distributable cash flow attributable to noncontrolling interest in OpCo	(72,352)		(85,093)		(181,677)		(249,669)
MLP distributable cash flow	$	14,886	$	17,879	$	34,607	$	51,906

Reconciliation of EBITDA to Net Income, Income from Operations and Net Cash Provided by Operating Activities

The following table presents reconciliations of EBITDA to net income, income from operations and net cash provided by operating activities, the most directly comparable GAAP financial measures, for each of the periods indicated.


	Three Months Ended September 30,				Nine Months Ended September 30,
	2025		2024		2025		2024

	(in thousands of dollars)
Net cash provided by operating activities	$	105,238	$	126,071	$	160,090	$	352,532
Loss from disposition of property, plant and equipment	(1,788)		(416)		(2,279)		(2,241)
Changes in operating assets and liabilities and other	(17,236)		(21,555)		56,507		(68,519)
Net income	86,214		104,100		214,318		281,772
Less:
Other income, net	224		1,325		2,245		3,916
Interest expense—Westlake	(5,947)		(6,698)		(17,391)		(19,930)
Provision for income taxes	(42)		(216)		(354)		(633)
Income from operations	91,979		109,689		229,818		298,419
Add:
Depreciation and amortization	33,872		28,112		93,424		84,421
Other income, net	224		1,325		2,245		3,916
EBITDA	$	126,075	$	139,126	$	325,487	$	386,756

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Summary

For the quarter ended September 30, 2025, net income was $86.2 million on net sales of $308.9 million. This represents a decrease in net income of $17.9 million as compared to net income of $104.1 million on net sales of $277.0 million for the quarter ended September 30, 2024. Net income attributable to the Partnership for the third quarter of 2025 was $14.7 million as compared to $18.1 million for the third quarter of 2024, a decrease of $3.4 million. Income from operations was $92.0 million for the third quarter of 2025 as compared to $109.7 million for the third quarter of 2024, a decrease of $17.7 million. Net sales for the third quarter of 2025 increased by $31.9 million as compared to the third quarter of 2024 primarily due to higher ethylene sales prices and sales volumes to Westlake, partially offset by lower ethylene and co-products sales prices and sales volumes to third parties. Income from operations, net income and net income attributable to the Partnership for the third quarter of 2025 as compared to the third quarter of 2024 were lower due to lower third-party sales prices and higher ethane feedstock and natural gas costs, partially offset by higher sales to Westlake in the third quarter of 2025 compared to the third quarter of 2024.

For the nine months ended September 30, 2025, net income was $214.3 million on net sales of $843.6 million. This represents a decrease in net income of $67.5 million as compared to net income of $281.8 million on net sales of $845.8 million for the nine months ended September 30, 2024. Net income attributable to the Partnership for the nine months ended September 30, 2025 was $34.2 million as compared to $47.4 million for the nine months ended September 30, 2024, a decrease of $13.2 million. Income from operations was $229.8 million for the nine months ended September 30, 2025 as compared to $298.4 million for the nine months ended September 30, 2024, a decrease of $68.6 million. Net sales for the nine months ended September 30, 2025 decreased by $2.2 million as compared to net sales for the nine months ended September 30, 2024, mainly due to lower ethylene and co-products sales volumes to Westlake and third parties as a result of lower production volumes attributable to the Petro 1 turnaround, partially offset by higher ethylene sales prices to Westlake and third parties as well as a buyer deficiency fee of $13.6 million recognized during the nine months ended September 30, 2025 as a result of a forecasted annual production deficiency due to the Petro 1 turnaround extending into April 2025, which was later than the planned completion in March 2025. Income from operations, net income and net income attributable to the Partnership for the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024 were lower primarily due to the lower sales volumes and higher ethane feedstock and natural gas costs during the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024.

RESULTS OF OPERATIONS

Third Quarter 2025 Compared with Third Quarter 2024

Net Sales. Net sales increased by $31.9 million, or 11.5%, to $308.9 million in the third quarter of 2025 from $277.0 million in the third quarter of 2024. The increase in net sales in the third quarter of 2025 as compared to the third quarter of 2024 was primarily due to higher ethylene sales prices and sales volumes to Westlake, partially offset by lower ethylene and co-products sales prices and sales volumes to third parties. Higher average sales prices in the third quarter of 2025 contributed to a 12.0% increase in net sales compared to the third quarter of 2024. Lower sales volumes in the third quarter of 2025 contributed to a 0.5% decrease in net sales compared to the third quarter of 2024.

Gross Profit. Gross profit decreased to $99.4 million in the third quarter of 2025 from $116.9 million in the third quarter of 2024. Gross profit margin in the third quarter of 2025 was 32.2%, as compared to 42.2% in the third quarter of 2024. The lower gross profit margin was primarily due to higher ethane feedstock and natural gas costs in the third quarter of 2025 compared to the third quarter of 2024.

Selling, General and Administrative Expenses. Selling, general and administrative expenses remained relatively consistent at $7.4 million in the third quarter of 2025 as compared to $7.3 million in the third quarter of 2024.

Interest Expense—Westlake. Interest expense of $5.9 million in the third quarter of 2025 decreased from $6.7 million in the third quarter of 2024 mainly due to lower interest rates on the outstanding debt in the third quarter of 2025 as compared to the third quarter of 2024.

Other Income, net. Other income, net decreased to $0.2 million in the third quarter of 2025 from $1.3 million in the third quarter of 2024, primarily due to a decrease in interest earned on investments with Westlake under the Investment Management Agreement due to a lower average amount of cash invested and lower interest rates in the third quarter of 2025 as compared to the third quarter of 2024.

MLP Distributable Cash Flow. MLP distributable cash flow decreased by $3.0 million to $14.9 million in the third quarter of 2025 from $17.9 million in the third quarter of 2024. The decrease in the third quarter of 2025, as compared to the prior-year period, was primarily attributable to decreased earnings at OpCo and higher maintenance capital expenditures.

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EBITDA. EBITDA decreased by $13.0 million to $126.1 million in the third quarter of 2025 from $139.1 million in the third quarter of 2024. The decrease was primarily due to lower third-party sales prices and higher ethane feedstock and natural gas costs, partially offset by higher sales to Westlake in the third quarter of 2025 compared to the third quarter of 2024.

Nine Months Ended September 30, 2025 Compared with Nine Months Ended September 30, 2024

Net Sales. Net sales decreased by $2.2 million, or 0.3%, to $843.6 million in the nine months ended September 30, 2025 from $845.8 million in the nine months ended September 30, 2024. The decrease in net sales in the nine months ended September 30, 2025 was primarily due to lower ethylene and co-products sales volumes to Westlake and third parties as a result of lower production volumes attributable to the Petro 1 turnaround, partially offset by higher ethylene sales prices to Westlake and third parties as well as a buyer deficiency fee of $13.6 million recognized during the nine months ended September 30, 2025 as a result of a forecasted annual production deficiency due to the Petro 1 turnaround extending into April 2025, which was later than the planned completion in March 2025. The higher average sales prices in the nine months ended September 30, 2025 contributed to a 10.1% increase in net sales compared to the nine months ended September 30, 2024. The lower sales volumes in the nine months ended September 30, 2025 contributed to an 11.9% decrease in net sales as compared to the nine months ended September 30, 2024.

Gross Profit. Gross profit decreased to $251.0 million in the nine months ended September 30, 2025 from $320.4 million in the nine months ended September 30, 2024. Gross profit margin in the nine months ended September 30, 2025 was 29.8%, as compared to 37.9% for the nine months ended September 30, 2024. The decrease in gross profit margin was primarily due to higher ethane feedstock and natural gas costs in the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024.

Selling, General and Administrative Expenses. Selling, general and administrative expenses decreased by $0.7 million, or 3.2%, to $21.2 million in the nine months ended September 30, 2025 as compared to $21.9 million in the nine months ended September 30, 2024. The decrease was mainly attributable to lower service costs in the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024.

Interest Expense—Westlake. Interest expense of $17.4 million in the nine months ended September 30, 2025 decreased by $2.5 million as compared to interest expense of $19.9 million in the nine months ended September 30, 2024. The decrease was primarily attributable to lower interest rates on the outstanding debt in the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024.

Other Income, net. Other income, net decreased by $1.7 million to $2.2 million in the nine months ended September 30, 2025 from $3.9 million in the nine months ended September 30, 2024, primarily due to a decrease in interest earned on investments with Westlake under the Investment Management Agreement due to a lower average amount of cash invested and lower interest rates in the nine months ended September 30, 2025 as compared to the nine months ended September 30, 2024.

MLP Distributable Cash Flow. MLP distributable cash flow decreased by $17.3 million to $34.6 million in the nine months ended September 30, 2025 from $51.9 million in the nine months ended September 30, 2024. The decrease in the nine months ended September 30, 2025, as compared to the prior-year period, was primarily attributable to lower ethylene and co-products sales volumes to Westlake and third parties as a result of lower production volumes attributable to the Petro 1 turnaround and higher maintenance capital expenditures due to the Petro 1 turnaround.

EBITDA. EBITDA decreased by $61.3 million to $325.5 million in the nine months ended September 30, 2025 from $386.8 million in the nine months ended September 30, 2024. The decrease was primarily due to higher ethane feedstock and natural gas costs and lower ethylene and co-products sales volumes to Westlake and third parties as a result of lower production volumes attributable to the Petro 1 turnaround. The decrease was partially offset by higher ethylene sales prices to Westlake and third parties as well as a buyer deficiency fee of $13.6 million recognized during the nine months ended September 30, 2025 as a result of a forecasted annual production deficiency due to the Petro 1 turnaround extending into April 2025, which was later than the planned completion in March 2025.

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CASH FLOW DISCUSSION FOR THE NINE MONTHS ENDED SEPTEMBER 30, 2025 AND 2024

Operating Activities

Operating activities provided cash of $160.1 million in the first nine months of 2025 compared to cash provided by operating activities of $352.5 million in the first nine months of 2024. The $192.4 million decrease in cash flows from operating activities was mainly due to cash used in connection with the Petro 1 turnaround, lower income from operations in the first nine months of 2025 as compared to the first nine months of 2024 and a decrease in cash provided by working capital. Changes in components of working capital, which we define for the purposes of this cash flow discussion as accounts receivable, net—Westlake, accounts receivable, net—third parties, inventories, prepaid expenses and other current assets less accounts payable—Westlake, accounts payable—third parties and accrued and other liabilities, used cash of $26.2 million in the first nine months of 2025 as compared to $1.2 million of cash provided in the first nine months of 2024, resulting in an overall unfavorable change of $27.4 million. The unfavorable change in working capital was mainly attributable to an unfavorable change in net accounts receivable—Westlake due to the buyer deficiency recognized in the first nine months of 2025 and lower receivables with Westlake outstanding as of the fourth quarter of 2024 due to sales of excess quantities of ethylene at a lower sales price. This unfavorable change was partially offset by favorable changes in accrued and other liabilities due to the impact of the Petro 1 turnaround activities and the timing of payments in the first nine months of 2025.

Investing Activities

Net cash provided by investing activities in the first nine months of 2025 was $50.0 million as compared to net cash used for investing activities of $50.5 million in the first nine months of 2024, resulting in an overall favorable change of $100.5 million in investing cash flows. During the first nine months of 2025, there were maturities of investments with Westlake of $120.0 million under the Investment Management Agreement, whereas during the first nine months of 2024, there were investments with Westlake of $15.0 million and no maturities under the Investment Management Agreement. Capital expenditures increased to $70.0 million in the first nine months of 2025 as compared to $35.5 million in the first nine months of 2024 due to the Petro 1 turnaround. Capital expenditures in the first nine months of 2025 and 2024 were primarily related to projects to increase production capacity or reduce costs, maintenance costs and safety and environmental projects at our facilities.

Financing Activities

Net cash used for financing activities in the first nine months of 2025 was $230.5 million as compared to net cash used for financing activities of $300.4 million in the first nine months of 2024. The cash outflows in the first nine months of 2025 were related to distributions of $180.6 million to the noncontrolling interest retained in OpCo by Westlake and of $49.8 million to unitholders by the Partnership. The cash outflows in the first nine months of 2024 were related to distributions of $250.6 million to the noncontrolling interest retained in OpCo by Westlake and of $49.8 million to unitholders by the Partnership.

LIQUIDITY AND CAPITAL RESOURCES

Liquidity and Financing Arrangements

Pursuant to the terms of the Equity Distribution Agreement, entered in October 2018 and amended in February 2020, among the Partnership and various investment banks, the Partnership may offer and sell the Partnership's common units from time to time to or through the investment banks, as the Partnership's sales agents or as principals, having an aggregate offering amount of up to $50.0 million (the "ATM Program"). The Partnership intends to use the net proceeds of sales of the common units, if any, for general partnership purposes, which may include the funding of potential drop-downs and other acquisitions. No common units had been issued under the ATM Program as of September 30, 2025.

Based on the terms of our cash distribution policy, we expect that we will distribute to our partners most of the excess cash generated by our operations. To the extent we do not generate sufficient cash flow to fund capital expenditures, we expect to fund them primarily from external sources, including borrowing directly from Westlake, as well as future issuances of equity interests or debt.

The Partnership maintains separate bank accounts, but Westlake continues to provide treasury services on our behalf under the Omnibus Agreement. Our sources of liquidity include cash generated from operations, the OpCo Revolver, the MLP Revolver and, if necessary and possible under then current market conditions, the issuance of additional equity interests or debt. We believe that cash generated from these sources will be sufficient to meet our short-term working capital requirements and long-term capital expenditure requirements and to make quarterly cash distributions. Westlake may also provide other direct and indirect financing to us from time to time, although it is not obligated to do so.

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In order to fund non-annual turnaround expenditures, we cause OpCo to reserve an amount for turnaround costs during each twelve-month period designed to cover future turnaround activities. Each of OpCo's ethylene production facilities requires turnaround maintenance approximately every five years. By reserving additional cash annually, we intend to reduce the variability in OpCo's cash flow. Westlake's purchase price for its minimum commitment of ethylene under the Ethylene Sales Agreement includes a component (adjusted annually) designed to cover, over the long term, substantially all of OpCo's turnaround expenditures.

Our cash is generated from cash distributions from OpCo. OpCo is a restricted subsidiary under certain indentures governing Westlake's senior notes, and these restrictions limit OpCo's ability to, among other things, incur additional debt. Westlake's credit facility and various indentures do not prevent OpCo from making distributions to us.

We, OpCo and Westlake are parties to an Investment Management Agreement that authorizes Westlake to invest the Partnership's and OpCo's excess cash with Westlake for durations of up to a maximum of nine months. Per the terms of the Investment Management Agreement, cash invested with Westlake earns a market return plus five basis points and Westlake provides daily availability of the invested cash to meet any liquidity needs of the Partnership or OpCo.

On October 28, 2025, the board of directors of Westlake Chemical Partners GP LLC, our general partner, approved a quarterly distribution of $0.4714 per common unit payable on November 26, 2025 to unitholders of record as of November 10, 2025, which equates to a total amount of approximately $16.6 million per quarter, or approximately $66.5 million per year in aggregate, based on the number of common units outstanding on September 30, 2025. We do not have a legal or contractual obligation to pay distributions on a quarterly basis or any other basis at our minimum quarterly distribution rate or any other rate.

Capital Expenditures

Westlake has historically funded expansion capital expenditures related to Lake Charles Olefins and Calvert City Olefins. No such funding was required by OpCo during the nine months ended September 30, 2025 and 2024. Total capital expenditures for the nine months ended September 30, 2025 and 2024 were $70.0 million and $35.5 million, respectively. We expect that Westlake will loan additional cash to OpCo to fund its expansion capital expenditures in the future, but Westlake is under no obligation to do so.

Cash and Cash Equivalents

As of September 30, 2025, our cash and cash equivalents totaled $37.9 million. In addition, we have cash invested under the Investment Management Agreement (as described below) and a revolving credit facility with Westlake available to supplement cash if needed, as described under "Indebtedness" below.

In August 2017, the Partnership, OpCo and Westlake executed the Investment Management Agreement that authorizes Westlake to invest the Partnership's and OpCo's excess cash with Westlake for durations of up to a maximum of nine months. Per the terms of the Investment Management Agreement, the Partnership earns a market return plus five basis points and Westlake provides daily availability of the invested cash to meet any liquidity needs of the Partnership or OpCo. The Partnership had $13.4 million of cash invested under the Investment Management Agreement at September 30, 2025.

Indebtedness

OpCo Revolver

In connection with the IPO, OpCo entered into a $600.0 million revolving credit facility with an affiliate of Westlake, as amended in June 2017, September 2018 and July 2022 (the "OpCo Revolver") that may be used to fund growth projects and working capital needs. The OpCo Revolver is scheduled to mature on July 12, 2027. On July 12, 2022, OpCo entered into the Second Amendment (the "OpCo Revolver Amendment") to the OpCo Revolver. The OpCo Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of the London Interbank Offered Rate ("LIBOR") with the Secured Overnight Financing Rate, as administered by the Federal Reserve Bank of New York ("SOFR"). Borrowings under the OpCo Revolver bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the OpCo Revolver is 1.75%. As of September 30, 2025, outstanding borrowings under the OpCo Revolver totaled $22.6 million and bore interest at SOFR plus the Applicable Margin and credit spread adjustment, which is accrued in arrears quarterly.

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MLP Revolver

In 2015, we entered into a senior, unsecured revolving credit agreement with an affiliate of Westlake, as amended in August and November 2017, March 2020 and July 2022 (the "MLP Revolver"). The MLP Revolver has a borrowing capacity of $600.0 million and is scheduled to mature on July 12, 2027. On July 12, 2022, the Partnership entered into the Fourth Amendment (the "MLP Revolver Amendment") to the MLP Revolver. The MLP Revolver Amendment, among other things, extended the maturity date to July 12, 2027 and provided for the replacement of LIBOR with SOFR as the reference rate. Borrowings under the MLP Revolver bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the MLP Revolver varies between 1.75% and 2.75%, depending on the Partnership's Consolidated Leverage Ratio. The MLP Revolver provides that we may pay all or a portion of the interest on any borrowings in kind, in which case any such amounts would be added to the principal amount of the loan. The MLP Revolver requires that we maintain a consolidated leverage ratio of either (1) during any one-year period following certain types of acquisitions (including acquisitions of additional interests in OpCo), 5.50:1.00 or less, or (2) during any other period, 4.50:1.00 or less. The MLP Revolver also contains certain other customary covenants. The repayment of borrowings under the MLP Revolver is subject to acceleration upon the occurrence of an event of default. As of September 30, 2025, outstanding borrowings under the MLP Revolver totaled $377.1 million and bore interest at SOFR plus the Applicable Margin and credit spread adjustment, which is accrued in arrears quarterly. We intend to use the MLP Revolver to purchase additional limited partnership interests in OpCo in the future, in the event OpCo desires to sell such additional interests to us, for other acquisitions and for general partnership purposes.

Off-Balance Sheet Arrangements

None.

Recent Accounting Pronouncements

See Note 1 to the consolidated financial statements included in Item 1 of this Form 10-Q for a full description of recent accounting pronouncements, including expected date of adoption and estimated effect on results of operations and financial condition.

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FORWARD-LOOKING STATEMENTS

Certain of the statements contained in this report are forward-looking statements. All statements, other than statements of historical facts, included in this report that address activities, events or developments that we expect, project, believe or anticipate will or may occur in the future are forward-looking statements. Forward-looking statements can be identified by the use of words such as "believes," "intends," "may," "should," "could," "anticipates," "expects," "will" or comparable terminology, or by discussions of strategies or trends. Although we believe that the expectations reflected in such forward-looking statements are reasonable, we cannot give any assurances that these expectations will prove to be correct. Forward-looking statements relate to matters such as:

•the amount of ethane that we are able to process, which could be adversely affected by, among other things, operating difficulties;

•the volume of ethylene that we are able to sell;

•the price at which we are able to sell ethylene;

•industry market outlook, including prices and margins in third-party ethylene and co-products sales;

•widespread outbreak of an illness or any other communicable disease, or any other public health crisis;

•the impact of ongoing supply chain constraints caused by the conflicts in the Middle East and between Russia and Ukraine;

•the parties to whom we will sell ethylene and on what basis;

•volumes of ethylene that Westlake may purchase, in addition to the minimum commitment under the Ethylene Sales Agreement;

•timing, funding and results of capital expenditures;

•our intended quarterly distributions and the manner of making such distributions;

•our ability to meet our liquidity needs;

•timing of and amount of capital expenditures;

•our At-the-Market program and the use of any net proceeds from any sales under that program;

•our and OpCo's ability to extend our credit agreements with Westlake;

•potential loans from Westlake to OpCo to fund OpCo's expansion capital expenditures in the future;

•expected mitigation of exposure to commodity price fluctuations;

•turnaround activities and the variability of OpCo's cash flow;

•receipt of any buyer deficiency fee and Shortfall under the Ethylene Sales Agreement;

•compliance with present and future environmental regulations and costs associated with environmentally related penalties, capital expenditures, remedial actions and proceedings, including any new laws, regulations or treaties that may come into force to limit or control carbon dioxide and other greenhouse gas emissions or to address other issues of climate change;

•our ability to receive indemnification from Westlake for environmental and other losses; and

•effects of pending legal proceedings.

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We have based these statements on assumptions and analysis in light of our experience and perception of historical trends, current conditions, expected future developments and other factors we believe were appropriate in the circumstances when the statements were made. Forward-looking statements by their nature involve substantial risks and uncertainties that could significantly impact expected results, and actual future results could differ materially from those described in such statements. These statements are subject to a number of assumptions, risks and uncertainties, including those described under "Risk Factors" in the 2024 Form 10-K and the following:

•general economic and business conditions, including inflation, interest rates and possible recession;

•the cyclical nature of the chemical industry;

•the availability, cost and volatility of raw materials and energy;

•lower crude oil prices reducing the cost advantage of ethane-based ethylene producers;

•actions taken by Westlake, including the renewal or renegotiation of, or determinations made pursuant to, our contractual arrangements with Westlake;

•uncertainties associated with the United States and worldwide economies, including those due to political tensions and conflict in the Middle East and elsewhere, including the conflict between Russia and Ukraine;

•uncertainties associated with pandemic infectious diseases;

•uncertainties associated with climate change;

•the potential impact on demand for ethylene due to initiatives such as recycling and customers seeking alternatives to polymers;

•current and potential governmental regulatory actions in the United States and regulatory actions and political unrest in other countries, including environmental regulations;

•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 (including leaks, explosions, fires, weather-related incidents, mechanical failure, unscheduled downtime, delays in turnaround activities, labor difficulties, transportation interruptions, spills and releases and other environmental risks);

•changes in laws or regulations;

•the effects of government shutdowns;

•technological developments;

•information systems failures and cyberattacks;

•our ability to implement our business strategies; and

•creditworthiness of our customers.

Many of these factors are beyond our ability to control or predict. Any of the 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 or projecting any future results based on such statements or present or prior earnings levels. 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.

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Item 3. Quantitative and Qualitative Disclosures about Market Risk

Commodity Price Risk

A substantial portion of the Partnership's products and raw materials are commodities whose prices fluctuate as market supply and demand fundamentals change. However, our direct exposure to commodity price risk is limited to approximately 5.0% of our total ethylene production, which is the portion sold to third parties. We believe we have substantially mitigated our indirect exposure to commodity price fluctuation during the term of the Ethylene Sales Agreement through the minimum purchase commitment and the cost-plus based pricing. Additionally, we may use derivative instruments to reduce price volatility risk on feedstocks and ethylene associated with the production and sales to third parties. We did not have any open derivative position at September 30, 2025.

Interest Rate Risk

We are exposed to interest rate risk with respect to our outstanding debt, all of which is variable rate debt. At September 30, 2025, we had variable rate debt of $399.7 million outstanding, all of which was owed to wholly-owned subsidiaries of Westlake. On July 12, 2022, OpCo entered into the OpCo Revolver Amendment. The OpCo Revolver Amendment, among other things, provided for the replacement of LIBOR with SOFR as the reference rate. Borrowings under the OpCo Revolver bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the OpCo Revolver is 1.75%. On July 12, 2022, the Partnership entered into the MLP Revolver Amendment. The MLP Revolver Amendment, among other things, provided for the replacement of LIBOR with SOFR as the reference rate. Borrowings under the MLP Revolver bear interest at a variable rate of either (a) SOFR plus the Applicable Margin plus a 0.10% credit spread adjustment or, if SOFR is no longer available, (b) the Alternate Base Rate plus the Applicable Margin minus 1.0%. The Applicable Margin under the MLP Revolver varies between 1.75% and 2.75%, depending on the Partnership's Consolidated Leverage Ratio. The weighted average variable interest rate of our debt as of September 30, 2025 was 6.1%. We will continue to be subject to interest rate risk with respect to our variable rate debt as well as the risk of higher interest cost if and when this debt is refinanced. A hypothetical increase in our average interest rate on variable rate debt by 100 basis points would increase our annual interest expense by approximately $4.0 million, of which $3.8 million would relate to the MLP Revolver and $0.2 million would relate to the OpCo Revolver based on the September 30, 2025 debt balance.

Item 4. Controls and Procedures

We carried out an evaluation, under the supervision and with the participation of our management, including our President and Chief Executive Officer and our Executive Vice President and Chief Financial Officer, of the effectiveness of our disclosure controls and procedures pursuant to Rules 13a-15 or 15d-15 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), as of the end of the period covered by this report. Based upon that evaluation, our President and Chief Executive Officer and our Executive Vice President and Chief Financial Officer concluded that our disclosure controls and procedures are effective with respect to (i) the accumulation and communication to our management, including our Chief Executive Officer and our Chief Financial Officer, of information required to be disclosed by us in the reports that we submit under the Exchange Act, and (ii) the recording, processing, summarizing and reporting of such information within the time periods specified in the SEC's rules and forms.

There were no changes in our internal control over financial reporting that occurred during the three months ended September 30, 2025 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II. OTHER INFORMATION

Item 1. Legal Proceedings

The 2024 Form 10-K, filed on March 5, 2025, contained a description of various legal proceedings in which we are involved, including environmental proceedings. See Note 12 to the unaudited consolidated financial statements within this Quarterly Report on Form 10-Q for an updated discussion of legal proceedings, which information is incorporated by reference herein.

Under the Omnibus Agreement, certain subsidiaries of Westlake Corporation ("Westlake") have agreed to indemnify the Partnership for certain environmental and other liabilities relating to OpCo's processing facilities and related assets that occurred or existed prior to August 4, 2014. Pursuant to the Services and Secondment Agreement, certain subsidiaries of Westlake have agreed to indemnify the Partnership for certain liabilities incurred in connection with the performance of Westlake's services under such agreement.

In addition to the matters described above, the Partnership is also involved in other legal proceedings incidental to the conduct of its business. After considering all relevant facts and circumstances, including applicable insurance and indemnification by Westlake, the Partnership does not believe that any of these legal proceedings will have a material adverse effect on its financial condition, results of operations or cash flows.

Item 1A. Risk Factors

For a discussion of risk factors, please read Item 1A, "Risk Factors" in the 2024 Form 10-K. There have been no material changes from those risk factors.

Item 5. Other Information

Rule 10b5-1 Trading Arrangements. During the three months ended September 30, 2025, no director or officer of the Partnership's general partner adopted or terminated a "Rule 10b5-1 trading arrangement" or "non-Rule 10b5-1 trading arrangement," as each term is defined in Item 408 of Regulation S-K.

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Item 6. Exhibits


Exhibit No.						Exhibit





3.1						Certificate of Limited Partnership of Westlake Chemical Partners LP (incorporated by reference to Exhibit 3.1 to Westlake Chemical Partners LP's Registration Statement on Form S-1 (File No. 333-195551), filed on April 29, 2014).

3.2						First Amended and Restated Agreement of Limited Partnership of Westlake Chemical Partners LP (incorporated by reference to Exhibit 3.1 to Westlake Chemical Partners LP's Current Report on Form 8-K (File No. 001-36567) filed on August 8, 2014).

3.3						Amendment No. 1 to the First Amended and Restated Agreement of Limited Partnership of Westlake Chemical Partners LP dated as of November 16, 2017 (incorporated by Reference to Exhibit 3.1 to Westlake Chemical Partners LP's Current Report on Form 8-K, filed on November 16, 2017, File No. 01-36567).

3.4						Amendment No. 2 to the First Amended and Restated Agreement of Limited Partnership of Westlake Chemical Partners LP (incorporated by reference to Exhibit 3.1 to Westlake Chemical Partners LP's Current Report on Form 8-K filed on July 30, 2018 (File No. 01-36567)).

3.5						Amended and Restated Agreement of Limited Partnership of Westlake Chemical OpCo LP (incorporated by reference to Exhibit 10.7 to Westlake Chemical Partners LP's Current Report on Form 8-K (File No. 001-36567) filed on August 8, 2014).

3.6						Amendment No. 1 to the Amended and Restated Agreement of Limited Partnership of Westlake Chemical OpCo LP dated as of December 1, 2017 (File No. 01-36567) (incorporated by reference to Exhibit 3.4 to Westlake Chemical Partners LP's Annual Report on Form 10-K for the year ended December 31, 2017 (File No. 01-36567) filed on March 1, 2018).

10.1						First Amendment to Services and Secondment Agreement by and among Westlake Chemical OpCo LP, Westlake Management Services, Inc., Westlake Vinyls, Inc., WPT LLC and Westlake Petrochemicals LLC (incorporated by Reference to Exhibit 10.2 to Westlake Chemical Partners LP's Current Report on Form 8-K, filed on October 30, 2025, File No. 01-36567).

10.2						First Amendment to the Omnibus Agreement among Westlake Management Services, Inc., Westlake Vinyl Corporation, Westlake Chemical Partners GP LLC, Westlake Chemical Partners LP, WPT LLC, Westlake Petrochemicals LLC, Westlake Vinyls, Inc., Westlake Longview Corporation, Westlake Chemical OpCo GP LLC, Westlake Chemical OpCo LP, Westlake PVC Corporation, Westlake Styrene LLC and Westlake Polymers LLC (incorporated by Reference to Exhibit 10.4 to Westlake Chemical Partners LP's Current Report on Form 8-K, filed on October 30, 2025, File No. 01-36567).

31.1†						Rule 13a – 14(a) / 15d – 14(a) Certification (Principal Executive Officer)

31.2†						Rule 13a – 14(a) / 15d – 14(a) Certification (Principal Financial Officer)

32.1#						Section 1350 Certification (Principal Executive Officer and Principal Financial Officer)

101.INS†						Inline XBRL Instance Document–The instance document does not appear in the interactive data file because its XBRL tags are embedded within the Inline XBRL document.

101.SCH†						Inline XBRL Taxonomy Extension Schema Document

101.CAL†						Inline XBRL Taxonomy Extension Calculation Linkbase Document

101.DEF†						Inline XBRL Taxonomy Extension Definition Linkbase Document

101.LAB†						Inline XBRL Taxonomy Extension Label Linkbase Document

101.PRE†						Inline XBRL Taxonomy Extension Presentation Linkbase Document

104						Cover Page Interactive Data File - The cover page interactive data file does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.

_____________

† Filed herewith.

# Furnished herewith.

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SIGNATURES

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 thereunto duly authorized.

WESTLAKE CHEMICAL PARTNERS LP

Date:

October 31, 2025

By:

/S/ JEAN-MARC GILSON

Jean-Marc Gilson

President, Chief Executive Officer and Director of
Westlake Chemical Partners GP LLC
(Principal Executive Officer)

Date:

October 31, 2025

By:

/S/ M. STEVEN BENDER

M. Steven Bender

Executive Vice President, Chief Financial Officer and
Director of Westlake Chemical Partners GP LLC
(Principal Financial Officer)

Westlake Chemical Partners LP 10-Q