Form 8-K

8-K — Montauk Renewables, Inc.

Accession: 0001193125-26-209194

Filed: 2026-05-06

Period: 2026-05-06

CIK: 0001826600

SIC: 4932 (GAS & OTHER SERVICES COMBINED)

Item: Results of Operations and Financial Condition

Item: Financial Statements and Exhibits

Documents

8-K — mntk-20260506.htm (Primary)

EX-99.1 (mntk-ex99_1.htm)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: mntk-20260506.htm · Sequence: 1

8-K

0001826600false00018266002026-05-062026-05-06

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 06, 2026

Montauk Renewables, Inc.

(Exact name of Registrant as Specified in Its Charter)

Delaware

001-39919

85-3189583

(State or Other Jurisdiction

of Incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

5313 Campbells Run Road

Suite 200

Pittsburgh, Pennsylvania

15205

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (412) 747-8700

(Former Name or Former Address, if Changed Since Last Report)

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

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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

Title of each class

Trading

Symbol(s)

Name of each exchange on which registered

Common Stock, par value $0.01 per share

MNTK

The Nasdaq Stock Market

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

Emerging growth company ☒

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

Item 2.02 Results of Operations and Financial Condition.

On May 6, 2026, Montauk Renewables, Inc. issued a press release announcing its financial results for the quarter ended March 31, 2026. A copy of the press release is furnished as Exhibit 99.1 to this report.

In accordance with General Instruction B.2 of Form 8-K, the information in Item 2.02 of this Current Report on Form 8-K, including Exhibit 99.1, shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liability of that section, and shall not be incorporated by reference into any registration statement or other document filed under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit

No. Description

99.1 Press release, dated May 6, 2026 of Montauk Renewables, Inc.

104 Cover Page Interactive Data File (embedded within the Inline XBRL document)

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 hereunto duly authorized.

MONTAUK RENEWABLES, INC.

Date:

May 6, 2026

By:

/s/ Kevin A. Van Asdalan

Name:

Title:

Kevin A. Van Asdalan

Chief Financial Officer

EX-99.1

Filename: mntk-ex99_1.htm · Sequence: 2

EX-99.1

Exhibit 99.1

Montauk Renewables Announces First Quarter 2026 Results

PITTSBURGH, PENNSYLVANIA – May 6, 2026—Montauk Renewables, Inc. (“Montauk” or “the Company”) (NASDAQ: MNTK), a renewable energy company specializing in the management, recovery, and conversion of biogas into renewable natural gas (“RNG”), today announced financial results for the first quarter ended March 31, 2026.

First Quarter Highlights:

• Revenues of $46.4 million, increased 9.0 % compared to the first quarter of 2025

• Net income increased $0.5 million, year-over-year

• Non-GAAP Adjusted EBITDA of $10.8 million, increased 22.8% year-over-year

• RNG production of 1.4 million MMBtu, flat compared to first quarter of 2025

• RINs sold of 12.4 million, increased 2.5 million or 25.5% year-over-year

In March 2026, we entered into a new, five year senior credit facility with a wholly owned subsidiary of Hannon Armstong Capital LLC ("HASI”) that consists of up to $200 million in senior indebtedness. We used this facility to refinance our existing outstanding debt and have $45 million available to borrow subject to terms of the agreement. Additionally, we successfully negotiated a five-year gas rights extension at our Raeger facility. The extension secures our access to biogas feedstock at the site through 2031, supporting the continued operation of the facility. The EPA finalized RFS standards for 2026 and 2027, as well as a partial waiver of the 2025 cellulosic biofuel volume requirement. Final cellulosic biofuel volume requirements for 2026 and 2027 were established at 1,360 million and 1,430 million D3 RINs, respectively, representing an increase from the preliminary RFS standards for 2026 and 2027.

We have commissioned our Montauk Ag Renewables project in North Carolina and expect our production and revenue generation activities to commence in May 2026. We expect a ramp-up in production volumes throughout 2026 directly related to additional feedstock collection.

First Quarter Financial Results

Total revenues in the first quarter of 2026 were $46.4 million, an increase of $3.8 million (9.0%) compared to $42.6 million in the first quarter of 2025. The increase is related to environmental attribute revenues from RINs sold related to the distribution of RINs from our GreenWave joint venture which had no RINs distributed and sold in the first quarter of 2025. Our first quarter of 2026 RNG volumes sold under fixed/floor-price contracts decreased approximately 82.1% as compared to first quarter of 2025 as a result of the expiration of fixed price pathway contracts. Our RNG commodity revenue decreased approximately 49.3% which was offset by an increase in RINs sold of 25.5%. Operating and maintenance expenses for our RNG facilities in the first quarter of 2026 were $14.4 million, an increase of $0.3 million (1.8%) compared to $14.1 million in the first quarter of 2025. Our Rumpke facility operating and maintenance expenses increased approximately $0.4 million primarily related to preventative maintenance media changes. Our Apex facility operating and maintenance expenses increased approximately $0.3 million primarily related to increased utility expense which was partially offset by decreased preventative maintenance media changes. Our Atascocita facility operating and maintenance expenses increased approximately $0.2 million primarily related to wellfield operational enhancements. Our Galveston facility operating and maintenance expenses decreased approximately $0.6 million primarily driven by the timing of maintenance of gas processing equipment and preventative maintenance media changes. Our Renewable Electricity Generation operating and maintenance expenses in the first quarter of 2026 were $4.5 million, an increase of $1.1 million (33.8%) compared to $3.4 million in the first quarter of 2025. The increase was primarily driven by an increase in non-capitalizable costs of $0.8 million for our Montauk Ag Renewables project and an increase in our Bowerman facility operating and maintenance expenses of approximately $0.4 million, primarily driven by the timing of gas processing preventative maintenance. We recorded approximately $4.2 million of expenses in the first quarter of 2026 related to the cost of RINs distributed from GreenWave and the costs related to pathway dispensing associated with our dispensing RNG in exclusive unique and proprietary pathways. Total general and administrative expenses were $8.0 million in the first quarter of 2026, a decrease of $0.7 million (8.4%) compared to $8.7 million in the first quarter of 2025 driven by vesting of certain restricted share awards in 2025. Operating loss in the first quarter of 2026 was $1.6 million compared to operating income of $0.4 million in the

first quarter of 2025. We recognized $3.3 million from our GreenWave joint venture in the first quarter of 2026. Net income in the first quarter of 2026 was $5 thousand compared to a net loss of $0.5 million in the first quarter of 2025.

First Quarter Operational Results

We produced 1.4 million Metric Million British Thermal Units (“MMBtu”) of RNG during the first quarter of 2026, flat compared to 1.4 million MMBtu produced in the first quarter of 2025. Our Galveston facility produced 41 thousand MMBtu fewer in the first quarter of 2026 compared to the first quarter of 2025 as a result of landfill host assuming responsibility of wellfield operations and maintenance beginning in the first quarter of 2026. Our McCarty facility produced 88 thousand MMBtu fewer in the first quarter of 2026 compared to the first quarter of 2025 as a result of landfill host wellfield bifurcation and changes to the wellfield collection system. Our Atascocita facility produced 43 thousand MMBtu more in the first quarter of 2026 compared to the first quarter of 2025 as a result of landfill host wellfield operational and collection system enhancements. Our Apex facility produced 37 thousand MMBtu more in the first quarter of 2026 as compared to first quarter of 2025 as a result of the June 2025 commissioning of our second Apex facility and increased feedstock gas from improvements we are making to the landfill collection system. We produced approximately 43 thousand megawatt hours (“MWh”) in Renewable Electricity in the first quarter of 2026, a decrease of 3 thousand MWh compared to 46 thousand MWh produced in the first quarter of 2025. Our Pico facility produced approximately 2 thousand MWh fewer in the first quarter of 2026 compared to the first quarter of 2025. The decrease is primarily related to decommissioning of one our engines in the second quarter of 2025 due to the shift towards boiler heat for our digestion process. Our Bowerman facility produced approximately 1 thousand MWh fewer in the first quarter of 2026 compared to the first quarter of 2025. The decrease is primarily related to the non-linear timing of original equipment manufacturer required lifecycle maintenance on our engines, beginning in the first quarter of 2026.

2026 Full Year Outlook

•

RNG revenues are expected to range between $175 and $190 million (unchanged)

•

RNG production volumes are expected to range between 5.8 and 6.0 million MMBtu (unchanged)

•

REG revenues are expected to range between $33 and $37 million

•

REG production volumes are expected to range between 195 and 207 thousand MWh (unchanged)

The reduction in REG revenues outlook relates to our current expectations on the commencement of revenue generation for our Montauk Ag Renewables facility.

Conference Call Information

The Company will host a conference call May 7, 2026 at 8:30 a.m. Eastern time to discuss results. The registration for the conference call will be available via the following link:

• https://register-conf.media-server.com/register/BIa109b4ab08264ba7b4aacd5776761b8f

Please register for the conference call and webcast using the above link in advance of the call start time. The webcast platform will register your name and organization as well as provide dial-ins numbers and a unique access pin. The conference call will be broadcast live and be available for replay at https://edge.media-server.com/mmc/p/yttdhevu/ and on the Company’s website at https://ir.montaukrenewables.com after 11:30 a.m. Eastern time on the same day through May 7, 2027.

Use of Non-GAAP Financial Measures

This press release and the accompanying tables include references to EBITDA and Adjusted EBITDA, which are Non-GAAP financial measures. We present EBITDA and Adjusted EBITDA because we believe the measures assist investors in analyzing our performance across reporting periods on a consistent basis by excluding items that we do not believe are indicative of our core operating performance.

In addition, EBITDA and Adjusted EBITDA are financial measurements of performance that management and the board of directors use in their financial and operational decision-making and in the determination of certain compensation programs. EBITDA and Adjusted EBITDA are supplemental performance measures that are not required by or presented in accordance with GAAP. EBITDA and Adjusted EBITDA should not be considered alternatives to net income (loss) or any other performance measure derived in accordance with GAAP, or as an alternative to cash flows from operating activities or a measure of our liquidity or profitability.

About Montauk Renewables, Inc.

Montauk Renewables, Inc. (NASDAQ: MNTK) is a renewable energy company specializing in the management, recovery and conversion of biogas into RNG. The Company captures methane, preventing it from being released into the atmosphere, and converts it into either RNG or electrical power for the electrical grid (“Renewable Electricity”). The Company, headquartered in Pittsburgh, Pennsylvania, develops, operates and manages landfill methane-fueled renewable energy projects. The Company has current operations at 13 operating projects and on going development projects located in California, Idaho, Ohio, Oklahoma, Pennsylvania, North Carolina, South Carolina, and Texas. The Company sells RNG and Renewable Electricity, taking advantage of Environmental Attribute premiums available under federal and state policies that incentivize their use. For more information, visit https://ir.montaukrenewables.com

Company Contact:

John Ciroli

Chief Legal Officer (CLO) & Secretary

investor@montaukrenewables.com

(412) 747-8700

Investor Relations Contact:

Georg Venturatos

Gateway Investor Relations

MNTK@gateway-grp.com

(949) 574-3860

Safe Harbor Statement

This release contains “forward-looking statements” within the meaning of U.S. federal securities laws that involve substantial risks and uncertainties. All statements other than statements of historical or current fact included in this report are forward-looking statements. Forward-looking statements refer to our current expectations and projections relating to our financial condition, results of operations, plans, objectives, strategies, future performance, and business. Forward-looking statements may include words such as “anticipate,” “assume,” “believe,” “can have,” “contemplate,” “continue,” “strive,” “aim,” “could,” “design,” “due,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “likely,” “may,” “might,” “objective,” “plan,” “predict,” “project,” “potential,” “seek,” “should,” “target,” “will,” “would,” and other words and terms of similar meaning in connection with any discussion of the timing or nature of future operational performance or other events. For example, all statements we make relating to our future results of operations, financial condition, expectations and plans, including those related to the Montauk Ag project in North Carolina, the GreenWave joint venture, the Bowerman RNG Facility, the development of a biogenic carbon dioxide facility and the related offtake, the Emvolon collaboration and pilot project, the Rumpke RNG Relocation project, the Tulsa facility project, the resolution of gas collection issues at the McCarty facility, the delays and cancellations of landfill host wellfield expansion projects, the mitigation of wellfield extraction environmental factors at the Rumpke and Apex facilities, how we may monetize RNG production and weather-related anomalies are forward-looking statements. All forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially from those that we expect and, therefore, you should not unduly rely on such statements. The risks and uncertainties that could cause those actual results to differ materially from those expressed or implied by these forward-looking statements include but are not limited to: our ability to develop and operate new renewable energy projects, including with livestock farms, and related challenges associated with new projects, such as achieving anticipated levels of energy output on a sustained basis on the announced timeline, identifying suitable locations, obtaining and refinancing or otherwise repaying acquisition financing and unexpected delays in construction and development; reduction or elimination of government loans, subsidies and other economic incentives to the renewable energy market, as a result of the current presidential administration and otherwise; the inability to complete strategic development opportunities; widespread manmade, natural and other disasters (including severe weather events), health emergencies, dislocations, geopolitical instabilities or events (including the current unrest in the Middle East), domestic protests and other forms of civil unrest, terrorist activities, international hostilities, government shutdowns, political elections, security breaches, cyberattacks or other extraordinary events that impact general economic conditions, energy markets, financial markets and/or our business and operating results; taxes, tariffs, duties or other assessments on equipment necessary to generate or deliver renewable energy or continued inflation that raise our operating costs and increase the construction costs of our existing or new projects; rising interest rates increase the borrowing costs of indebtedness; the failure to attract and retain qualified personnel or a possible increased reliance on third-party contractors as a result, and the potential unenforceability of non-compete clauses with our employees; the length of development and optimization cycles for new projects, including the design and construction processes for our livestock farm and other renewable energy projects; dependence on third parties for the manufacture of products and services and our landfill operations; the quantity, quality and consistency of our feedstock volumes from both landfill and livestock farm operations; reliance on interconnections with and access to electric utility distribution and transmission facilities and gas transportation pipelines for our Renewable Natural Gas and Renewable Electricity Generation segments; our ability to renew pathway provider sharing arrangements at historical counterparty share percentages; our projects not producing expected levels of output; potential benefits associated with the combustion-based oxygen removal condensate neutralization technology; concentration of revenues from a small number of customers and projects; our outstanding indebtedness, ability to refinance indebtedness at acceptable rates or at all and restrictions under existing and future indebtedness; our ability to extend our fuel supply agreements prior to expiration; our ability to meet milestone requirements under our power purchase agreements; existing regulations and changes to regulations and policies that effect our operations; expected impacts of the Production Tax Credit and other tax credit benefits under the Inflation Reduction Act of 2022; decline in public acceptance and support of renewable energy development and projects; our expectations regarding Environmental Attribute volume requirements and prices and commodity prices; our expectations regarding the period during which we qualify as an emerging growth company under the Jumpstart Our Business Startups Act (“JOBS Act”); our expectations regarding future capital expenditures, including for the maintenance of facilities; our expectations regarding the use of net operating losses before expiration; our expectations regarding more attractive carbon intensity scores by regulatory agencies for our livestock farm projects; market volatility and fluctuations in commodity prices and the market prices of Environmental Attributes and the impact of any related hedging activity; regulatory changes in federal, state and international environmental attribute programs and the need to obtain and maintain regulatory permits, approvals, and consents; profitability of our planned livestock farm projects; sustained demand for renewable energy; potential liabilities from contamination and environmental conditions; potential exposure to costs and liabilities due to extensive environmental, health and safety laws; impacts of climate change, extreme and changing weather patterns and conditions and natural disasters; failure of our information technology and data security systems; increased competition in our markets; ability to keep up with technology innovations; concentrated stock ownership by a few stockholders and related control over the outcome of all matters subject to a stockholder vote; and other risks and uncertainties detailed in the section titled “Risk Factors” in our latest Annual Report on Form 10-K and our other filings with the SEC.

We make many of our forward-looking statements based on our operating budgets and forecasts, which are based upon detailed assumptions. While we believe that our assumptions are reasonable, we caution that it is very difficult to predict the impact of known factors, and it is impossible for us to anticipate all factors that could affect our actual results. All forward-looking statements attributable to us are expressly qualified in their entirety by these cautionary statements as well as others made in our Securities and Exchange Commission filings and public communications. You should evaluate all forward-looking statements made by us in the context of these risks and uncertainties. The forward-looking statements included herein are made only as of the date hereof. We undertake no obligation to publicly update or revise any forward-looking statement as a result of new information, future events, or otherwise, except as required by law

MONTAUK RENEWABLES, INC.

CONSOLIDATED BALANCE SHEETS

(Unaudited)

(in thousands, except share data)

as of March 31,

as of December 31,

ASSETS

2026

2025

Current assets:

Cash and cash equivalents

25,947

23,752

Accounts and other receivables

5,226

9,167

Current restricted cash

Income tax receivable

622

702

Current portion of derivative instruments

—

220

Prepaid insurance and other current assets

3,888

3,306

Total current assets

35,691

37,155

Non-current restricted cash

2,725

430

Property, plant and equipment, net

371,490

341,395

Goodwill and intangible assets, net

19,337

19,605

Deferred tax assets

5,930

5,550

Operating lease right-of-use assets

8,226

9,082

Finance lease right-of-use assets

Equity method investment

3,774

3,824

Other assets

20,587

18,380

Total assets

467,780

435,460

LIABILITIES AND STOCKHOLDERS' EQUITY

Current liabilities:

Accounts payable

27,446

15,638

Accrued liabilities

11,620

11,735

Current portion of operating lease liability

2,899

3,287

Current portion of finance lease liability

Current portion of long-term debt

—

2,733

Total current liabilities

41,978

33,425

Long-term debt, less current portion

149,494

126,000

Non-current portion of operating lease liability

5,423

5,880

Non-current portion of finance lease liability

Asset retirement obligations

7,087

6,960

Other liabilities

Total liabilities

204,007

172,312

STOCKHOLDERS’ EQUITY

Common stock, $0.01 par value, authorized 690,000,000 shares; 143,912,811 shares issued at March 31, 2026 and December 31, 2025; 143,244,544 shares outstanding at March 31, 2026 and December 31, 2025

1,431

Treasury stock, at cost, 2,521,886 shares March 31, 2026 and December 31, 2025

(21,681

)

(21,681

)

Additional paid-in capital

226,922

226,302

Retained earnings

57,101

57,096

Total stockholders' equity

263,773

263,148

Total liabilities and stockholders' equity

467,780

435,460

MONTAUK RENEWABLES, INC.

CONSOLIDATED STATEMENTS OF OPERATIONS

(Unaudited)

(in thousands, except share and per share data)

Three Months Ended March 31,

2026

2025

Total operating revenues

46,428

42,603

Operating expenses:

Operating and maintenance expenses

23,155

17,557

General and administrative expenses

8,019

8,754

Royalties, transportation, gathering and production fuel

8,037

7,571

Depreciation, depletion and amortization

8,373

6,264

Impairment loss

443

2,047

Total operating expenses

48,027

42,193

Operating (loss) income

(1,599

)

410

Other expenses (income):

Interest expense

1,336

1,243

Income from equity investment

(3,320

)

—

Loss on extinguishment of debt

944

—

Other income

(266

)

(52

)

Total other (income) expenses

(1,306

)

1,191

Loss before income taxes

(293

)

(781

)

Income tax benefit

(298

)

(317

)

Net income (loss)

(464

)

Income (loss) per share:

Basic

0.00

(0.00

)

Diluted

0.00

(0.00

)

Weighted-average common shares outstanding:

Basic

143,244,544

142,711,797

Diluted

143,258,120

142,711,797

MONTAUK RENEWABLES, INC.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(Unaudited)

(in thousands)

Three Months Ended March 31,

2026

2025

Cash flows from operating activities:

Net income (loss)

(464

)

Adjustments to reconcile net income to net cash provided by operating

activities:

Depreciation, depletion and amortization

8,373

6,264

Benefit for deferred income taxes

(380

)

(333

)

Loss on extinguishment of debt

944

—

Stock-based compensation

635

1,274

Derivative mark-to-market adjustments and settlements

220

214

Net (gain) loss on sale or disposal of assets

(13

)

Decrease in earn-out liability

—

(425

)

Accretion of asset retirement obligations

127

118

Amortization of debt issuance costs

142

Impairment loss

443

2,047

Non-cash expense - RINs from equity method investment

3,370

—

Income from equity method investment

(3,320

)

—

Cash provided (used) by changes in assets and labilities:

Accounts receivable

3,941

(319

)

Royalty offset long term receivable

(2,132

)

(739

)

Income tax receivable

(215

)

Critical spare inventory

(131

)

(303

)

Accounts payable and Accrued liabilities

3,916

2,213

Other

(374

)

(304

)

Net cash provided by operating activities

15,846

9,140

Cash flows from investing activities:

Capital expenditures

(30,867

)

(11,632

)

Proceeds from sale of assets

—

Net cash used in investing activities

(30,834

)

(11,632

)

Cash flows from financing activities:

Repayments of long-term debt

(44,000

)

(3,000

)

Borrowings of long-term debt

155,000

—

Repayments of revolver

(105,000

)

—

Borrowings of revolver

20,000

—

Debt extinguishment costs

(944

)

—

Debt issuance costs

(5,560

)

—

Finance lease payments

(18

)

(18

)

Net cash provided (used) in financing activities

19,478

(3,018

)

Net increase (decrease) in cash and cash equivalents and restricted cash

4,490

(5,510

)

Cash and cash equivalents and restricted cash at beginning of period

24,190

46,004

Cash and cash equivalents and restricted cash at end of period

28,680

40,494

Reconciliation of cash, cash equivalents, and restricted cash at end of period:

Cash and cash equivalents

25,947

40,111

Restricted cash and cash equivalents - current

Restricted cash and cash equivalents - non-current

2,725

375

28,680

40,494

Supplemental cash flow information:

Cash paid for interest, net of $1,579 and $0 capitalized respectively

1,853

1,055

Cash paid for income taxes

319

Accrual for purchase of property, plant and equipment included in accounts payable and accrued liabilities

19,562

8,534

Non-cash RIN distribution from equity method investment

3,370

—

MONTAUK RENEWABLES, INC.

NON-GAAP FINANCIAL MEASURES

(Unaudited)

(in thousands):

The following table provides our EBITDA and Adjusted EBITDA, as well as a reconciliation to net income (loss) which is the most directly comparable GAAP measure for the three months ended March 31, 2026 and 2025, respectively:

Three Months Ended March 31,

2026

2025

Net income (loss)

(464

)

Depreciation, depletion and amortization

8,373

6,264

Interest expense

1,336

1,243

Income tax benefit

(298

)

(317

)

Consolidated EBITDA

9,416

6,726

Impairment loss

443

2,047

Loss on extinguishment of debt

944

—

Net (gain) loss on disposal of assets

(13

)

Adjusted EBITDA

10,790

8,788

XML — IDEA: XBRL DOCUMENT

XML

Filename: R1.htm · Sequence: 5

v3.26.1

Document And Entity Information

May 06, 2026

Cover [Abstract]

Document Type

8-K

Amendment Flag

false

Document Period End Date

May 06, 2026

Entity Registrant Name

Montauk Renewables, Inc.

Entity Central Index Key

0001826600

Entity Emerging Growth Company

true

Entity File Number

001-39919

Entity Incorporation, State or Country Code

Entity Tax Identification Number

85-3189583

Entity Address, Address Line One

5313 Campbells Run Road

Entity Address, Address Line Two

Suite 200

Entity Address, City or Town

Pittsburgh

Entity Address, State or Province

Entity Address, Postal Zip Code

15205

City Area Code

(412)

Local Phone Number

747-8700

Written Communications

false

Soliciting Material

false

Pre-commencement Tender Offer

false

Pre-commencement Issuer Tender Offer

false

Entity Ex Transition Period

false

Title of 12(b) Security

Common Stock, par value $0.01 per share

Trading Symbol

MNTK

Security Exchange Name

NASDAQ

- Definition

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

+ References

No definition available.

+ Details

Name:

dei_AmendmentFlag

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Area code of city

+ References

No definition available.

+ Details

Name:

dei_CityAreaCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Cover page.

+ References

No definition available.

+ Details

Name:

dei_CoverAbstract

Namespace Prefix:

dei_

Data Type:

xbrli:stringItemType

Balance Type:

Period Type:

duration

- Definition

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

+ References

No definition available.

+ Details

Name:

dei_DocumentPeriodEndDate

Namespace Prefix:

dei_

Data Type:

xbrli:dateItemType

Balance Type:

Period Type:

duration

- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

+ Details

Name:

dei_DocumentType

Namespace Prefix:

dei_

Data Type:

dei:submissionTypeItemType

Balance Type:

Period Type:

duration

- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine1

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Address Line 2 such as Street or Suite number

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine2

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the City or Town

+ References

No definition available.

+ Details

Name:

dei_EntityAddressCityOrTown

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Code for the postal or zip code

+ References

No definition available.

+ Details

Name:

dei_EntityAddressPostalZipCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Name of the state or province.

+ References

No definition available.

+ Details

Name:

dei_EntityAddressStateOrProvince

Namespace Prefix:

dei_

Data Type:

dei:stateOrProvinceItemType

Balance Type:

Period Type:

duration

- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityCentralIndexKey

Namespace Prefix:

dei_

Data Type:

dei:centralIndexKeyItemType

Balance Type:

Period Type:

duration

- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityEmergingGrowthCompany

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 7A

-Section B

-Subsection 2

+ Details

Name:

dei_EntityExTransitionPeriod

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

Name:

dei_EntityFileNumber

Namespace Prefix:

dei_

Data Type:

dei:fileNumberItemType

Balance Type:

Period Type:

duration

- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

+ Details

Name:

dei_EntityIncorporationStateCountryCode

Namespace Prefix:

dei_

Data Type:

dei:edgarStateCountryItemType

Balance Type:

Period Type:

duration

- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityRegistrantName

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityTaxIdentificationNumber

Namespace Prefix:

dei_

Data Type:

dei:employerIdItemType

Balance Type:

Period Type:

duration

- Definition

Local phone number for entity.

+ References

No definition available.

+ Details

Name:

dei_LocalPhoneNumber

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

+ Details

Name:

dei_PreCommencementIssuerTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14d

-Subsection 2b

+ Details

Name:

dei_PreCommencementTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b

+ Details

Name:

dei_Security12bTitle

Namespace Prefix:

dei_

Data Type:

dei:securityTitleItemType

Balance Type:

Period Type:

duration

- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection d1-1

+ Details

Name:

dei_SecurityExchangeName

Namespace Prefix:

dei_

Data Type:

dei:edgarExchangeCodeItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14a

-Subsection 12

+ Details

Name:

dei_SolicitingMaterial

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration

- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

Name:

dei_TradingSymbol

Namespace Prefix:

dei_

Data Type:

dei:tradingSymbolItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

+ Details

Name:

dei_WrittenCommunications

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

duration