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ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The discussion and analysis of our financialcondition and results of operations for each of the years ended December 31, 2025 and 2024 are based on, and should be read in conjunction with, our audited Consolidated Financial Statements and the related notes included elsewhere in this 2025 Annual Report on Form 10-K. For a discussion and analysis of changes from 2023 to 2024 and other financial information related to prior periods, refer to Part II, Item 7. “Management’s Discussion and Analysis of Financial Condition and Results of Operations” included in our 2024 Annual Report on Form 10-K. The following discussion contains forward-looking statements that include risks and uncertainties. For a description of limitations inherent in forward-looking statements, see “Special Note Regarding Forward-Looking Statements” on page i and Part I, Item 1A. “Risk Factors” in this Report.

All dollar amounts included in the tables that follow are presented in thousands unless otherwise indicated. Certain variances presented as changes in year over year amounts that represent results that are not meaningful are indicated as “NM.”

Overview

We rent, design, install, service and maintain natural gas and electric compressors and related equipment for oil and gas production and processing facilities, generally using equipment from third-party fabricators and OEM suppliers. Substantially all of our compressor assembly is done by third-party contractors while a limited level of assembly work remains in-house at our Tulsa, Oklahoma facility. Our primary focus is on the rental of natural gas engine and electric motor drive compressors. Our rental agreements generally provide for initial terms of 12 to 60 months, with our large horsepower units having longer initial terms than our small and medium horsepower units. After the initial term of our rental agreements, most of our customers have continued to rent our compressors on a month-to-month basis. Rental amounts are billed monthly in advance and include maintenance of the rented compressor units.

We conduct our operations in several oil and gas producing basins throughout the U.S. including the Permian, Barnett Shale, Anadarko, San Juan, Utica/Marcellus Shale, Eagle Ford Shale and Antrim Shale. We have operating facilities in five states including Texas, Oklahoma, New Mexico, Michigan and Ohio. A total of 78 percent of our rental revenue is generated from the Permian Basin and approximately 90 percent of our rental revenue supports oil production primarily in the form of gas lift operations. We operate in one reporting segment.

State of the Industry and Outlook

Our strategy for growth is focused on our compressor rental business. Gross margins, exclusive of depreciation and amortization, for our rental business have historically been in the mid-50 percent to low-60 percent range, while margins for the compressor sales and aftermarket services businesses tend to be substantially lower.

The oil and gas equipment rental and services industry is cyclical in nature. The most critical factor in assessing the outlook for the industry is the worldwide supply and demand for oil and gas and the corresponding changes in commodity prices. As demand and prices increase, oil and gas producers typically increase their capital expenditures for drilling, development and production activities, although recent equity capital constraints and demands from institutional investors to keep spending within operating cash flow have meaningfully restrained capital expenditure budgets of domestic E&P companies. Generally, increased capital expenditures result in greater revenues and profits for service and equipment companies.

Generally, sustained higher commodity prices lead to higher capital expenditures by oil and gas producers and higher levels of production. In general, we expect our overall business activity and revenues to track the level of activity in the oil and gas industry, specifically production levels, with changes in crude oil and condensate production and consumption levels and prices affecting our business more than changes in domestic natural gas production and consumption levels and prices. In recent years we have increased our rentals in unconventional oil shale plays, which are more dependent on crude oil prices. With this shift towards oil production the demand for overall compression services and products is driven by two general factors; (i) an increased focus by producers on artificial lift applications, e.g., production enhancement with compression assisted gas lift; and (ii) declining reservoir pressure in maturing natural gas producing fields, especially non-conventional production. These latter types of applications have historically been serviced by wellhead size compressors, and continue to be, but there has also been an economic move by our customers towards centralized drilling and production facilities, which have increased the market need for single and multiple larger horsepower compressor packages. We recognized this need in recent years and have shifted our capital program towards acquiring compressor packages that range from 400 horsepower up to 2,500 horsepower for rental to our customers. While this is a response to market conditions and trends, it also provides us with the opportunity to compete as a full-line compression service provider.

We typically experience a decline in demand during periods of low oil and gas prices. In recent years, our level of activity has become more largely driven by the price of crude oil as opposed to natural gas. Generally, we feel that the level of demand for our compressor services is more closely tied to production activities, which are likely to fare better than drilling activity in periods of declining commodity prices.

Operating Highlights

The following table summarizes our key operating statistics as of the dates or for the periods presented, as applicable:

December 31,

Horsepower utilization (at period end) 84.9 % 82.1 % 80.8 %

Average horsepower utilization 83.6 % 81.8 % 78.2 %

Unit utilization (at period end) 65.0 % 63.2 % 66.5 %

Rental revenues as a percent of total revenues 95.4 % 92.0 % 87.6 %

Of the total horsepower utilized as of December 31, 2025, 464,137 of horsepower was being rented under contracts expiring between 2026 and 2030 and 98,539 of that horsepower was being rented on a month-to-month basis. Of the 1,245 compressors utilized as of December 31, 2025, 754 were being rented under multi-year contracts and 491 were being rented on a month-to-month basis.

Our Performance Trends and Outlook

The oil and gas industry has historically been cyclical and production levels of oil and gas are dependent upon numerous factors. The market for compression equipment and services is highly dependent on the production levels and pricing of oil and gas.

Crude Oil. The level of production for crude oil activity and capital expenditures has generally been dependent upon the prevailing view of future crude oil prices, which are influenced by numerous supply and demand factors, including availability and cost of capital, well productivity and development costs, global and domestic economic conditions, environmental regulations, policies of OPEC and Russia, and other factors. While crude oil prices have historically been volatile, we expect demand for our existing compressor fleet to remain positive assuming crude oil prices remain within reasonable bands with respect to current pricing levels.

Natural Gas. We believe the market outlook for natural gas production in the U.S. remains steady while short term price volatility remains a factor due to geopolitical influences and shifts in LNG exports. We believe opportunities for increased utilization of our small and medium horsepower units are supported by continued investment in shale gas development, particularly in the Permian basin and the Utica and Marcellus Shales.

Non-GAAP Financial Measures

We utilize certain financial and operating metrics to analyze our performance and assess our operating results and overall profitably and liquidity. The most significant of these measure are “Adjusted Gross Margin” and “Adjusted EBITDA” both of which are measurements that are not explicitly defined in accordance with generally accepted accounting principles in the United States of America (“GAAP”), or non-GAAP financial measures, and may vary among different industries and the participants therein.

Adjusted Gross Margin

We define “Adjusted Gross Margin” as total revenue less costs of revenues (excluding depreciation and amortization expense). Adjusted gross margin is included as a supplemental disclosure because it is a primary measure used by our management as it represents the results of revenue and costs (excluding depreciation and amortization expense), which are key components of our operations. Adjusted gross margin differs from gross margin, in that gross margin includes depreciation and amortization expense. We believe Adjusted gross margin is important because it focuses on the current operating performance of our operations and excludes the impact of the prior historical costs of the assets acquired or constructed that are utilized in those operations. Depreciation and amortization expense does not accurately reflect the costs required to maintain and replenish the operational usage of our assets and therefore may not portray the costs from current operating activity. Rather, depreciation and amortization expense reflects the systematic allocation of historical property and equipment costs over their estimated useful lives.

Adjusted gross margin has certain material limitations associated with its use as compared to gross margin. These limitations are primarily due to the exclusion of depreciation and amortization expense, which is material to our results of operations. Because we use capital assets, depreciation and amortization expense is a necessary element of our costs and our ability to generate revenue. In order to compensate for these limitations, management uses this non-GAAP measure as a supplemental measure to other GAAP results to provide a more complete understanding of our performance.

As an indicator of our operating performance, Adjusted gross margin should not be considered an alternative to, or more meaningful than, gross margin as determined in accordance with GAAP. Our Adjusted gross margin may not be comparable to a similarly titled measure of another company because other entities may not calculate Adjusted gross margin in the same manner.

The following table calculates our gross margin, the most directly comparable GAAP financial measure, and reconciles it to Adjusted gross margin with further detail by revenue classification for the periods presented:

Year Ended December 31,

Adjusted gross margin by revenue classification:

Adjusted EBITDA

“Adjusted EBITDA” is a non-GAAP financial measure that we define as net income before interest, taxes, depreciation and amortization, as well as an increase in inventory allowance, impairments, retirement of rental equipment, non-recurring restructuring charges including severance and non-cash equity-classified stock-based compensation expenses. This term, as used and defined by us, may not be comparable to similarly titled measures employed by other companies and is not a measure of performance calculated in accordance with GAAP. Adjusted EBITDA should not be considered in isolation or as a substitute for operating income, net income, cash flows provided by operating, investing and financing activities, or other income or cash flow statement data prepared in accordance with GAAP. However, management believes Adjusted EBITDA is useful to an investor in evaluating our operating performance because:

•it is widely used by investors in the energy industry to measure a company’s operating performance without regard to items excluded from the calculation of Adjusted EBITDA, which can vary substantially from company to company depending upon accounting methods and book value of assets, capital structure and the method by which assets were acquired, among other factors;

•it helps investors to more meaningfully evaluate and compare the results of our operations from period to period by removing the impact of our capital structure and asset base from our operating structure; and

•it is used by our management for various purposes, including as a measure of operating performance, in presentations to our Board of Directors, as a basis for strategic planning and forecasting, and as a component for setting incentive compensation.

Adjusted EBITDA has limitations as an analytical tool, and you should not consider it in isolation, or as a substitute for analysis of our results as reported in accordance with GAAP. Some of these limitations are:

•Adjusted EBITDA does not reflect all our cash expenditures, future requirements for capital expenditures, or contractual commitments;

•Adjusted EBITDA does not reflect changes in, or cash requirements for, our working capital needs;

•Adjusted EBITDA does not reflect the cash requirements necessary to service interest or principal payments on our debts; and

•although depreciation and amortization are non-cash charges, the assets being depreciated and amortized will often have to be replaced in the future, and Adjusted EBITDA does not reflect any capital expenditures for such replacements.

There are other material limitations to using Adjusted EBITDA as a measure of performance, including the inability to analyze the impact of certain recurring items that materially affect our net income or loss, and the lack of comparability of results of operations of different companies. Please read the table below to see how Adjusted EBITDA reconciles to our net income, the most directly comparable GAAP financial measure.

The following table reconciles our net income, the most directly comparable GAAP financial measure, to Adjusted EBITDA for the periods presented:

Year Ended December 31,

Interest income (2,444) — —

Retirement of rental equipment 728 28 505

Severance and restructuring charges 89 33 1,224

Results of Operations

Year Ended December 31, 2025 Compared to the Year Ended December 31, 2024

Rental

We generate revenue from renting, maintaining and servicing compressors to our customers under contractual arrangements. The underlying rental service agreements, which all qualify as operating leases under GAAP, generally include a fee for servicing the compressor unit as well as surcharges for fluids during the rental term. Our rental agreement terms typically range from 12 to 60 months. Our revenue is recognized over time, with monthly payments over the term of the agreement. After the terms of the agreement have expired, a customer may renew its agreement or continue renting on a monthly basis thereafter. The primary costs associated with providing our compressor fleet to our customers includes routine maintenance and repairs, fluids, primarily motor oils, and labor and related support costs for our field service facilities and service employees that are geographically dispersed throughout our operating regions.

The following table summarizes the revenues, costs, adjusted gross margin and related operating statistics with respect to our rentals of compressors for the periods presented:

Year Ended December 31,

Rental adjusted gross margin percentage 60.6 % 60.5 % 0.1 %

Percent of total company revenues 95.4 % 92.0 % 3.4 %

Horsepower utilization (at period end) 84.9 % 82.1 % 2.8 %

Rental revenue increased for the year ended December 31, 2025, as compared to 2024 due primarily to an increase in rented horsepower and units utilized. The increase in revenue reflects a continuing trend of growing demand for our large horsepower units (400 horsepower and greater) which provide for higher rental rates and realized adjusted gross margins. Our utilized horsepower increased during 2025 as compared to 2024 which reflects the continued addition of large horsepower units to our fleet consistent with our emphasis on larger units over the past several years, as well as the retirement of certain medium and small horsepower units from the fleet partially offset by the return of small horsepower units to the idle fleet by certain customers at the end of their lease terms. During the year ended December 31, 2025, we placed into service a total of 434 newly set units, including 364 from our existing fleet and 70 new units. Of those unit sets, a total of 126 were large horsepower units and 70 of those were new units to the fleet.

The cost of rentals increased on an absolute basis, consistent with revenues, due to the effects of supporting a larger quantity of utilized horsepower and inflationary pressures primarily in labor and parts costs. An expanding portion of our rented compressor units utilize our proprietary System Management and Recovery Technology (“SMART”) and telemetry software which reduces unplanned shutdowns and increases productivity. Despite inflationary pressure associated with our primary cost components, the SMART and telemetry technology allows us to streamline and manage our maintenance activities more efficiently and thereby mitigate the costs to a manageable extent. As a result of these factors, our adjusted gross margin increased on both an absolute basis as well as a percentage of revenues for the year ended December 31, 2025, compared to the year ended December 31, 2024.

Sales

We generate revenue primarily from the sale of compressor parts. Costs of sales include purchases of component materials. In addition, our costs of sales include overhead and related support costs attributable to our storage and assembly, facilities including Midland, Texas through its closure at the end of March 2025.

The following table summarizes the revenues, costs and adjusted gross margin with respect to our sales of compressors, parts and equipment and repair/overhaul services for the periods presented:

Year Ended December 31,

Sales adjusted gross margin $ (241) $ (290) $ 49 NM

Sales adjusted gross margin percentage (6.0) % (3.8) % (2.2) %

Percent of total company revenues 2.3 % 4.9 % (2.6) %

Sales revenue declined for the year ended December 31, 2025, as compared to 2024 due primarily to the phasing out of direct sales of compressors and rebuild work which was the primary focus of the former Midland Facility. While the costs to support our sales revenues declined on an absolute basis, primarily reflecting a lower volume of business, the adjusted gross margin improved marginally due primarily to the absence of indirect labor and fixed overhead costs that are not otherwise subject to capitalization subsequent to the closure of the former facility in Midland, Texas which we closed at the end of March 2025. Sales represented an insignificant portion of our overall gross margins in 2025 and 2024.

Aftermarket Services

We provide routine or call-out services on customer-owned equipment as well as commissioning of new units for customers. Revenue is recognized after services in the contract are rendered. The primary costs associated with our aftermarket services are labor, support costs, materials and supplies.

The following table summarizes the revenues, costs and adjusted gross margin with respect to our aftermarket services for the periods presented:

Year Ended December 31,

Aftermarket services adjusted gross margin $ 1,184 $ 943 $ 241 25.6 %

Aftermarket services adjusted gross margin percentage 29.6 % 19.3 % 10.3 %

Percent of total company revenues 2.3 % 3.1 % (0.8) %

Aftermarket services revenues and costs declined for the year ended December 31, 2025, compared to 2024; however, the absolute gross margin and percentage both improved as compared to 2024. The decline in revenues and costs is primarily attributable to a lower volume of unit commissioning work performed during 2025 compared to 2024 as well as the effects of lower freight costs. Aftermarket services represented an insignificant portion of our overall gross margins in 2025 and 2024.

Selling, General and Administrative Expenses

Our selling, general and administrative (“SG&A”) expenses include compensation and benefits, including stock-based compensation, commissions and other support costs of departments serving administrative and corporate governance functions, such as executive management, finance and accounting, sales and marketing, procurement, logistics and supply chain, human resources, information technology (“IT”), health, safety and environmental and investor relations. In addition, SG&A includes non-personnel costs, such as rent and occupancy, IT support, professional fees and other supporting corporate expenses including public company compliance costs.

The following table summarizes the components of our SG&A expenses for the periods presented:

Year Ended December 31,

SG&A expenses as a percent of total revenues 13.0 % 13.4 % (0.4) %

SG&A expenses increased for the year ended December 31, 2025, as compared to 2024 on an absolute dollar basis and declined marginally as a percent of total revenues. In general, the increase in primary SG&A expenses reflects a higher level of cost to appropriately scale our administrative function. The increase in primary SG&A expenses during 2025 as compared to 2024was impacted by (i) higher IT support costs of $1.0 million in support of our growth initiatives and noncapitalizable costs associated with certain IT system conversion projects, (ii) higher salaries and benefits of $0.8 million reflecting support staff growth and (iii) higher occupancy and office costs of $0.2 million. These increases were partially offset by (i) lower commissions of $0.5 million and (ii) lower credit loss expenses of $0.2 million. Our equity classified stock-based compensation increased during in 2025 over 2024 due primarily to a higher mix of performance-based share unit awards, or PSUs, for our executive officers in the 2025 period. PSUs generally have a higher grant-date fair value than traditional restricted stock and restricted stock unit awards.

Depreciation and Amortization

Depreciation and amortization expenses reflect the depreciation of our rental compressor fleet as well as the depreciation and amortization of our operating and corporate facilities, vehicles and other equipment, and the amortization of finance leases and intangible assets.

The following table summarizes the components of our depreciation and amortization expenses for the periods presented:

Year Ended December 31,

Depreciation and amortization allocable to cost of revenues:

Intangible asset amortization — 121 (121) NM

Depreciation and amortization as a percent of total revenues 21.3 % 20.0 % 1.3 %

Depreciation and amortization expense increased on an absolute basis during the year ended December 31, 2025, compared to 2024, due primarily to depreciation expense associated with the large horsepower units placed in service during the second half of 2024 continuing through the end of 2025. These large horsepower unit additions, which began in earnest during 2023, are reflective of our strategic plans to concentrate our business development on these higher margin applications.

Impairments

We assess our long-lived assets for impairment on an annual basis or when indicators of impairment are present. An impairment loss is recognized if the future undiscounted cash flows associated with the asset (or asset group) and the estimated fair value of the asset are less than the asset’s carrying value.

The following table indicates the charges incurred for impairments for the periods presented:

Year Ended December 31,

In connection with our efforts to plan for an eventual sale of the Former Headquarters Property, we undertook certain actions in the fourth quarter of 2025 to begin building-out a new leased office facility in Midland, Texas. While the Former Headquarters Property remained in use as of December 31, 2025, these actions triggered a review for impairment of the Former Headquarters Property consistent with our plans to relocate to the new leased facility in 2026. In our evaluation for the impairment, the cash flows that we considered were those that we expect to receive from a sale of the Former Headquarters Property, less costs to sell, or fair value. As the carrying value of the Former Headquarters Property exceeded the fair value less costs to sell, we recognized an impairment of $2.6 million in the fourth quarter of 2025. Subsequently, we entered into an exclusive listing agreement in February 2026 for the sale of the Former Headquarters Property. Please see Note 7 (“Property and Equipment”) and Note 19 (“Subsequent Events”) to our Consolidated Financial Statements for additional information. During 2024, we fully impaired an intangible asset attributable to a trade name for $0.7 million. Consistent with our shift in focus away from the sales of compressor and related technology, we determined that we will no longer market the technology associated with the trade name. In addition, we fully impaired certain IT assets in the amount of $0.2 million for which we terminated plans to develop and utilize the associated applications.

Inventory Allowance

We routinely review our stock of inventory for obsolescence and realizability. When the carrying value exceeds the net realizable value, a charge is recorded to operating income.

The following table indicates the charges incurred for inventory allowance for the periods presented:

Year Ended December 31,

During 2025, we recorded an increase of $1.1 million to the allowance for obsolescence primarily attributable to limitations on our ability to market certain assembled parts as well as the transfer of inventory that remains useful from our former Midland, Texas facility, in connection with its closing in March 2025, to our other operating facilities. Due primarily to the slow-moving nature, obsolescence of our long-term inventory and inventory related to the retirement of certain rental equipment, we recorded an increase of $1.9 million to the inventory allowance reserve for the year ended December 31, 2024. We ended 2025 with an inventory allowance balance of $3.6 million. Please see Note 4 (“Inventory”) to our Consolidated Financial Statements for additional information regarding the inventory allowance.

Retirement of Rental Equipment

We routinely review the rental fleet to determine which units are no longer of the type, configuration, make or model that our customers are demanding or that are not cost efficient to refurbish, maintain and/or operate. When appropriate, we retire such units from the fleet and write-off any remaining carrying value.

The following table indicates the charges incurred for the retirement of rental equipment for the periods presented:

Year Ended December 31,

Retirement of rental equipment $ 728 $ 28 $ 700 NM

We retired over 12,000 horsepower of small and medium horsepower compressor units during 2025 with only those units retired having any remaining carrying value. Such retirements were minimal during 2024.

Gain on Disposition of Assets

As circumstances warrant, we will market certain property and equipment, primarily trucks, when we have determined that there is no longer a productive use for such assets or favorable opportunities arise to monetize otherwise idle assets. Gains and losses are recognized accordingly upon the completion of such transactions.

The following table presents the gains recognized upon the disposition of assets for the periods presented:

Year Ended December 31,

Gain on the disposition of assets, net $ 270 $ 430 $ (160) (37.2) %

Gains recognized during the years ended December 31, 2025 and 2024 are primarily attributable to the sales of trucks after the completion of their useful lives.

Interest Expense

Interest expense primarily reflects the costs of borrowing, including commitment fees and the amortization of debt issue costs, under our Credit Facility, net of amounts capitalized attributable to certain capital projects. Also included is interest expense on our financing leases during 2024 as all were settled before 2025.

The following table presents the components of our interest expense for the periods presented:

Year Ended December 31,

Weighted-average interest rates on borrowings 7.31 % 8.82 % (1.51) %

Interest expense increased during the year ended December 31, 2025, as compared to 2024 due primarily to the effect of $2.3 million lower capitalized interest as a result of the volume and timing of the completion of certain compressor assembly projects during 2025. In addition, amortization of debt issue costs increased during 2025 as compared to 2024 due primarily to the amortization of costs associated with certain amendments to the Credit Facility that took place in June of 2024 as well as the Fourth Amendment to the Amended and Restated Credit Agreement (the “Fourth Amendment”) that was completed in April 2025. While the average borrowings outstanding under our Credit Facility have increased during 2025 as compared 2024, we experienced lower average interest rates consistent with the Federal Reserve interest rate reductions implemented in the second halves of 2024 and 2025 as well as the lower interest rates at comparable leverage levels attributable to the Fourth Amendment.

Interest Income

This component of our income reflects interest earned on investments and certain financial assets including, when applicable, interest on significant income tax refunds receivable.

The following table indicates our interest income for the periods presented:

Year Ended December 31,

Interest income for the year ended December 31, 2025 is entirely attributable to interest earned on certain income tax refunds for 2015, 2016, 2017 and 2019. The income tax refunds, including interest, for these tax years were substantially determined and settled in the first quarter of 2026. Please see Note 11 (“Income Taxes”) to our Consolidated Financial Statements for additional information.

Other Income (Expense), net

This component of our income primarily reflects non-operating items of income and loss including non-cash gains and losses attributable to our corporate-owned life insurance (“COLI”) policies related to our deferred compensation plan as well as other credits, charges and scrap asset sales. Please see Note 12 (“Deferred Compensation Plan”) to our Consolidated Financial Statements for additional information regarding the deferred compensation plan.

The following table indicates our other income (expense) for the periods presented:

Year Ended December 31,

Other income (expense), net improved for 2025 as compared to 2024 due primarily to certain non-operating credits and scrap asset sales as well as unrealized gains attributable to our COLI policies associated with our deferred compensation plan.

Provision for Income Taxes

Provision for income taxes represents our income taxes as determined in accordance with GAAP. It considers taxes attributable to our obligations for federal taxes under the IRC as well as to various states in which we operate, primarily Texas. Please see Note 11 (“Income Taxes”) to our Consolidated Financial Statements for additional information.

The following table summarizes our income tax provision for the periods presented:

Year Ended December 31,

Income tax expense increased for the year ended December 31, 2025, compared to 2024 due primarily to substantially higher pre-tax income during 2025 and the impact of a higher effective tax rate attributable to state and local income taxes. Our effective tax rate for both years differs from the U.S. federal statutory rate of 21%.

Financial Condition

Liquidity and Capital Resources

Our primary sources of liquidity include cash provided by operating activities and borrowings under our Credit Facility. On April 18, 2025, we entered into the Fourth Amendment which provides us with up to $400.0 million in borrowing commitments with an additional $100.0 million at our request through an accordion feature. The accordion feature is subject to certain conditions, including the absence of a default, the consent of new or existing lenders willing to provide additional commitments, and our pro forma compliance with the Credit Facility’s financial covenants. As of December 31, 2025, the borrowing base under the Credit Facility was $400.0 million with $230.0 million of borrowings outstanding leaving $170.0 million of availability under the Credit Facility.

Our cash flows from operating and investing activities are subject to a degree of volatility due primarily to (i) the consistency of our customers in remitting amounts owed to us for our services in full and on a timely basis and (ii) the timing of payments to our vendors and suppliers for capital projects which are often made well in advance of placing new compressor equipment into service. In order to mitigate such volatility we employ disciplined efforts to monitor customer credit and maintain communications to support collection efforts when necessary. To the extent necessary, we rely on the availability of our Credit Facility to fund capital expenditures beyond that provided by our cash flows from operating activities.

Our forecasted capital expenditures for 2026 will continue to be directly dependent upon our customers’ compression requirements and our capital availability, while maintaining prudent levels of debt.

The level of our capital expenditures will vary in future periods depending on energy market conditions and other related economic factors. Based upon existing economic and market conditions, we believe that cash on hand, cash flows from operating activities and borrowings under the Credit Facility will be sufficient to satisfy our capital, dividend and liquidity requirements for at least the twelve months subsequent to the date that this Annual Report on Form 10-K was filed. We also believe we have flexibility with respect to our financing alternatives and can make adjustments to our capital expenditure plans if circumstances warrant. We do not have any material continuing commitments related to our current operations that cannot be met with our cash on hand, cash from operating activities and borrowings under our Credit Facility.

If we require additional capital to fund any significant unanticipated expenditures, including any material acquisitions of other businesses, joint ventures or other opportunities, this additional capital could exceed our current resources and might not be available to us when we need it, or might not be on acceptable terms. In addition, our financing capacity could be negatively impacted by other economic factors. Please see Part I, Item 1A, “Risk Factors”, of this Report.

For a detailed analysis of our historical capital expenditures, see the “Cash Flows” discussion that follows.

Cash From Operating Activities. Our cash provided by operating activities was $62.9 million. For additional information and an analysis of or historical cash flows from operating activities, see the “Cash Flows” discussion that follows.

Credit Facility Borrowings. During 2025, we borrowed $60.0 million, net of repayments, under the Credit Facility. The following table summarizes our borrowing activity under the Credit facility for the periods presented:

Borrowings Outstanding

End of Period Weighted-average Maximum Weighted-average Rate

For additional information regarding the terms and covenants under the Credit Facility, see the “Capitalization” discussion that follows.

Proceeds from Sales and Monetization of Assets. We continually evaluate the potential sale of assets, including underutilized or retired compressor units, obsolete and slow-moving inventory and non-strategic real estate assets, among others. For additional information and an analysis of or historical proceeds from sales of assets, see the “Cash Flows” discussion that follows.

Capital Markets Transactions. From time-to-time and under market conditions that we believe are favorable to us, we may consider capital markets transactions, including the offering of debt and equity securities. We maintain an effective shelf registration statement with the SEC for up to $200 million for a variety of securities to provide financing optionality.

Cash Flows

The following table summarizes our cash flows for the periods presented:

Year Ended December 31,

Net cash provided by operating activities $ 62,927 $ 66,463

Net cash used in investing activities (121,297) (71,440)

Net cash provided by financing activities 56,228 4,373

Net decrease in cash and cash equivalents $ (2,142) $ (604)

Cash Flows from Operating Activities. Our cash flows from operating activities decreased by $3.5 million during 2025 from 2024. From a broad perspective, cash flows declined in 2025 due primarily to the substantial progress made in the 2024 period for improving our processes for billings and collections from certain customers that had the effect of lowering our days sales outstanding (“DSO”) statistics for accounts receivable accounts. While these efforts have continued with favorable DSO performance throughout 2025, the timing effect was more beneficial during 2024 while 2025 reflects a more normalized cash operating cycle. In addition, we increased our maintenance parts inventory during 2025 in support of our growing fleet and incurred substantially higher costs in 2025 attributable to certain IT system conversion projects. These working capital uses were partially offset by growth in accounts payable and the favorable effects of higher realized margins attributable to growth in our high horsepower unit rentals.

Cash Flows from Investing Activities. For the years ended December 31, 2025 and 2024, we invested approximately $121.5 millionand$71.9 million, respectively, in rental equipment, property and other equipment. Included in these totals for 2025 and 2024 were $109.8 million and $60.5 million for growth capital expenditures to expand our rental fleet and $11.7 million and $11.4 million for capital maintenance projects, respectively. Our investment in rental equipment includes any changes to work-in-progress related to our rental fleet projects at the beginning of the year compared to the end of the year. We also received proceeds from the sale of property and equipment of $0.1 million and $0.5 million in 2025 and 2024, respectively, as well as insurance proceeds from damage to certain rental equipment of $0.1 million during 2025.

Cash Flows from Financing Activities. During 2025, we had net borrowings of $60.0 million under the Credit Facility while 2024 included net borrowings of $6.0 million. The increase in net borrowings is due primarily to the substantial investment in large horsepower units during the prior year consistent with our expanding fleet and strategy of directing our business to these larger, higher margin applications. While we incurred and paid debt issuance costs during both years, the amounts paid during 2024 were $0.3 million higher in connection with the Fourth Amendment during 2025 as compared to the costs for amendments to the Credit Facility in 2024. During 2025 we also paid $2.6 million for our common stock dividend which was initiated for the third quarter of 2025 and continued in the fourth quarter. We also received proceeds from the exercise of stock options of $0.2 million and $0.3 million during 2025 and 2024, respectively.

Capitalization

The following table summarizes our total capitalization as of the dates presented:

December 31,

Debt as a percent of total capitalization 45.6 % 40.0 %

Credit Facility. We have a senior secured revolving credit agreement, as amended, or the Credit Facility, with Texas Capital Bank, National Association as administrative agent (the “Administrative Agent”), and TCBI Securities, Inc., Bank of America, N.A., and the Huntington National Bank as joint lead arrangers and joint book runners, and the lenders party thereto (the “Lenders”), with a total commitment of $400.0 million. We also have a right to request from the Lenders, an increase to the potential aggregate commitment of up to $100.0 million; provided, however, the aggregate commitment amount is not permitted to exceed $500.0 million. The obligations under the Credit Facility are secured by a first priority lien on most of our assets, including inventory and certain accounts receivable as well as a variable number of our leased compressor units. The maturity date of the Credit Facility is February 28, 2028.

Our Credit Facility is subject to: (i) a borrowing base calculation, (ii) variable rates of interest on borrowings that are determined, in part, upon our actual leverage ratio, as defined in the Credit Facility, (iii) commitment fees, (iv) certain financial and other covenants and (v) events of default and acceleration, among other terms and conditions that are customary for such credit instruments. Please see Note 10 (“Long-Term Debt”) to our Consolidated Financial Statements for a thorough discussion of these matters regarding our Credit Facility.

As of December 31, 2025, we had $230.0 million outstanding under our Credit Facility with a weighted average interest rate of 6.59%. As of December 31, 2025, we had approximately $170.0 million available for borrowing under the Credit Facility, subject to borrowing base determination. As of December 31, 2025, we were in compliance with all financial covenants in our Credit Facility.

Critical Accounting Estimates

We describe our significant accounting policies in Note 2 (“Summary of Significant Accounting Policies”) to our Consolidated Financial Statements. We believe that the application of these policies on a consistent basis enables us to provide the users of our financial statements with useful and reliable information regarding our results of operations, financial condition and cash flows.

The preparation of our Consolidated Financial Statements in conformity with GAAP requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, expenses and related disclosures. In the ordinary course of business, we have made a number of estimates and assumptions relating to the reporting of results of operations and financial condition in the preparation of our Consolidated Financial Statements. We evaluate our estimates and assumptions on an ongoing basis. Our estimates are generally based on historical experience and various other assumptions that we believe to be reasonable in consideration of our circumstances and expectations for the future based on available information. Our actual results could differ significantly from those estimates under different assumptions and conditions.

We consider an accounting estimate to be critical if: (i) the accounting estimate requires us to make assumptions about matters that were highly uncertain at the time the accounting estimate was made, and (ii) changes in the estimate that are reasonably likely to occur from period to period or use of different estimates that we reasonably could have used in the current period, would have a material impact on our financial condition or results of operations.

We believe that the following discussion addresses our most critical accounting estimates, which are those that are most important to the portrayal of our results of operations, financial condition and cash flows and require our most difficult, subjective, and complex judgments, often as a result of the need to make estimates about the effect of matters that are inherently uncertain.

Inventories

We value our total inventory (current and long-term) at the lower of the actual cost and net realizable value. We regularly review inventory quantities on hand and record an allowance for excess and obsolete inventory based primarily on current and anticipated customer demand and production requirements. We assess anticipated customer demand based on current and upcoming capital expenditure budgets of our major customers as well as other significant participants in the industry, along with oil and gas price forecasts and other factors affecting the industry as a whole. Our estimates and assumptions regarding these factors are subject to significant variability and can result in provisions for valuation allowances of our inventory. For the year ended December 31, 2025, our provision for excess and obsolete inventory totaled $1.1 million which increased our allowance for obsolescence to $3.6 million as described more fully in the discussion of our Results of Operations above and Note 4 (“Inventory”) to our Consolidated Financial Statements.

Long-Lived Assets

Depreciation

Depreciation expense is computed using the straight-line method over the estimated useful lives of the underlying long-lived assets. Our rental equipment has estimated useful lives ranging from 15 to 25 years, while our property and equipment has estimated useful lives which range from 3 to 39 years. The estimated useful lives and salvage values of these long-lived assets are based on estimates and assumptions that reflect our historical experience and expectations regarding their future utilization, obsolescence, technical developments, market demand and geographic location. The use of different estimates and assumptions in the determination of depreciation, particularly with respect to useful lives, could result in significant differences to our results of operations. We regularly review the appropriateness of the estimated useful lives of our long-lived assets and may shorten or extend such lives as appropriate based on business circumstances.

Impairments

We assess our long-lived assets, including rental equipment, other property and equipment and intangible assets for impairment whenever events or changes in circumstances indicate that the net carrying values may not be recoverable. The following factors could trigger an impairment review: significant underperformance relative to historical or projected future cash flows; significant adverse changes in the extent or manner in which an asset (or asset group) is being used or its condition, including a meaningful decline in fleet utilization over prior periods; significant negative industry or company-specific trends or actions, including meaningful capital expenditure budget reductions by our major customers or other sizable exploration and production or midstream organizations, as well as significant declines in oil and natural gas prices; legislative changes prohibiting us from leasing our units; or poor general economic conditions. After the assessments of such circumstances, an impairment loss is recognized if the future undiscounted net cash flows associated with the asset (or asset group) and the estimated fair value of the asset are less than the asset’s (or asset group’s) carrying value. During the year ended December 31, 2025, we recognized an impairment of $2.6 million in connection with our efforts to plan for an eventual sale of the Former Headquarters Property. Please see Note 7 (“Property and Equipment”) and Note 19 (“Subsequent Events”) to our Consolidated Financial Statements for additional information..

Income Taxes

In connection with the process of preparing our financial statements, we are required to estimate our federal income taxes as well as income taxes in each of the states in which we operate. This process involves us estimating our actual current tax exposure together with assessing temporary differences resulting from differing treatment of items for income tax and accounting purposes. These differences result in deferred tax assets and liabilities, which are reflected on our Consolidated Balance Sheets. We must then assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe that recovery is not probable, we must establish a valuation allowance. To the extent we establish a valuation allowance or increase this allowance during a period, we must include an expense in the tax provision in the Statement of Operations.

Significant management judgment is required in determining our provision for income taxes, our deferred tax assets and liabilities and any valuation allowance recorded against our net deferred tax assets. In this process, we consider all available positive and negative evidence including scheduled reversals of deferred tax liabilities, projected future taxable income, tax planning strategies and recent results of operations. As of December 31, 2025, we have no valuation allowance and fully expect to utilize all of our deferred tax assets.

Please see Note 11 (“Income Taxes”) for a more thorough discussion of our income taxes.

Off-Balance Sheet Arrangements

From time-to-time, we enter into off-balance sheet arrangements and transactions that can give rise to off-balance sheet obligations. As of December 31, 2025, we did not have any material off-balance sheet arrangements.

Recently Issued Accounting Pronouncements

Please see Note 2 (“Summary of Significant Accounting Policies”) to our Consolidated Financial statements for a discussion of recently issued accounting pronouncements.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

Market risk is the risk of loss arising from adverse changes in market rates and prices. The principal market risk to which we are exposed is interest rate risk.

Our interest rate risk is attributable to our borrowings under the Credit Facility, which are subject to variable interest rates. As of December 31, 2025, we had borrowings of $230.0 million under the Credit Facility at a weighted average interest rate of 6.59%. Assuming a constant borrowing level under the Credit Facility and excluding any changes in other financial metrics that would impact the applicable margin applied to Credit Facility borrowings, an increase (decrease) in the interest rate of one percent would result in an increase (decrease) in interest expense of $2.3 million on an annual basis.

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

The information required by this Item is presented in Part IV, Item 15. “Exhibits and Financial Statement Schedules” of this Annual Report on Form 10-K.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

None.

ITEM 9A. CONTROLS AND PROCEDURES

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer (“CEO”) and Chief Financial Officer (“CFO”), evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2025. We maintain “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, that are designed to ensure that information required to be disclosed in the reports that we file or submit under the Exchange Act is (i) recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms and (ii) accumulated and communicated to our management, including our principal executive officer and principal financial officer, to allow timely decisions regarding required disclosure. Based upon the evaluation, our CEO and CFO concluded that, as of such date, our disclosure controls and procedures were effective to provide reasonable assurance that the information required to be disclosed in reports that we file or submit under the Exchange Act is accumulated and communicated to management, and made known to our CEO and CFO, on a timely basis to ensure that it is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms.

Management’s Annual Report on Internal Control Over Financial Reporting

Our management, including the CEO and CFO, is responsible for establishing and maintaining adequate internal control over financial reporting (“ICFR”), as defined in Rule 13a-15(f) and 15d-15(f) under the Exchange Act. Our management conducted an evaluation of the effectiveness of the Company’s internal control over financial reporting as of December 31, 2025, based on the Internal Control – Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. Based on the results of management’s evaluation described above, management concluded that our ICFR was effective as of December 31, 2025.

Ham, Langston & Brezina LLP, an independent registered public accounting firm, has issued an attestation report on the effectiveness of the Company’s ICFR as of December 31, 2025, which included in Part IV, Item 15 “Exhibits and Financial Statement Schedules”of this Annual Report on Form 10-K.

Changes in Internal Control Over Financial Reporting

During the quarter ended December 31, 2025, there were no changes in our ICFR that have materially affected, or are reasonably likely to materially affect, our ICFR.

ITEM 9B. OTHER INFORMATION

Stephen C. Taylor, a member of the Board of Directors, adopted a Rule 10b5-1 trading agreement that is intended to satisfy the affirmative defense of Rule 10b5-1(c) for the sale of up to an aggregate of 100,000 shares of the Company’s common stock, subject to various volume amounts and price thresholds. The 10b5-1 Plan was entered into during an open insider trading window in December 2025 and sales commenced under the plan after completion of the required cooling off period under Rule 10b5-1.The plan became effective on March 5, 2026 and the aggregate sales were completed by March 6, 2026.

No other director or officer of the Company adopted, modified or terminated a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as each term is defined in Item 408(a) of Regulation S-K, during the three months ended December 31, 2025.

ITEM 9C. DISCLOSURES REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

None.

PART III

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

The information required by this item is incorporated herein by reference to the sections “Election of Directors,” “Executive Officers,” “Corporate Governance” and “The Board of Directors and its Committees” in our definitive proxy statement which will be filed with the SEC within 120 days after December 31, 2025, or as such period may be extended by action of the SEC.

We have adopted a Code of Business Conduct and Ethics that applies to our directors, officers and employees. The Code of Business Conduct and Ethics is posted in the “Investor Relations” section of our website at www.ngsgi.com. The Code of Business Conduct and Ethics may be obtained free of charge by writing before to Natural Gas Services Group, Inc., Attn: Investor Relations, 601 State Street, Suite 400, Southlake, TX 76092.

ITEM 11. EXECUTIVE COMPENSATION

The information required by this item is incorporated herein by reference to the section “Executive Compensation” in our definitive proxy statement which will be filed with the SEC within 120 days after December 31, 2025, or as such period may be extended by action of the SEC.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND

RELATED STOCKHOLDER MATTERS

The information required by this item is incorporated herein by reference to the section “Principal Shareholders and Security Ownership of Management” in our definitive proxy statement which will be filed with the SEC within 120 days after December 31, 2025, or as such period may be extended by action of the SEC.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTORINDEPENDENCE

The information required by this item is incorporated herein by reference to the sections “Related Person Transactions” and “Corporate Governance” in our definitive proxy statement which will be filed with the SEC within 120 days after December 31, 2025, or as such period may be extended by action of the SEC.

ITEM 14. PRINCIPAL ACCOUNTANT FEES AND SERVICES

The information required by this item is incorporated herein by reference to the section “Principal Accountant Fees and Services” in our definitive proxy statement which will be filed with the SEC within 120 days after December 31, 2025, or as such period may be extended by action of the SEC.

PART IV

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

(a) The following documents are filed as part of this Annual Report on Form 10-K.

1.Consolidated Financial Statements. The following financial statements are filed as a part of this Annual Report on Form 10-K:

Reports of Independent Registered Public Accounting Firm (PCAOB ID 298) F-1

Consolidated Balance Sheets F-3

Consolidated Statements of Operations F-4

Consolidated Statements of Stockholders’ Equity F-5

Consolidated Statements of Cash Flows F-6

Notes to Consolidated Financial Statements F-7

2. Financial Statement Schedules

All financial statement schedules have been omitted because they are not applicable or the information is set forth in the Consolidated Financial Statements or Notes thereto.

3. Exhibits

A list of exhibits to this Annual Report on Form 10-K is set forth below:

Exhibit No.Description

21.1* Subsidiaries of the Registrant.

23.1* Consent of Ham, Langston & Brezina L.L.P.

101.INS XBRL Instance Document.

101.SCH XBRL Taxonomy Extension Schema Document.

101.CAL XBRL Taxonomy Extension Calculation Linkbase Document.

101.DEF XBRL Taxonomy Extension Definition Linkbase Document.

101.LAB XBRL Taxonomy Extension Label Linkbase Document.

101.PRE XBRL Taxonomy Extension Presentation Linkbase Document.

† Management contract or compensatory plan or arrangement.

* Filed herewith.

ITEM 16. FORM 10-K SUMMARY

None.

SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) 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.

NATURAL GAS SERVICES GROUP, INC.

March 16, 2026 By: /s/ Justin C. Jacobs

Justin C. Jacobs

Chief Executive Officer

(Principal Executive Officer)

POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS,that each person whose signature appears below constitutes and appoints Justin C. Jacobs and Ian M. Eckert, jointly and severally, as his/her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him/her and in his/her name, place and stead, in any and all capacities, to sign any and all amendments to this Annual Report on Form 10-K and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents full power and authority to do and perform each and every act and thing requisite or necessary to be done in and about the premises hereby ratifying and confirming all that said attorneys-in-fact and agents, or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated:

Signature Title Date

Justin C. Jacobs

Ian M. Eckert

/s/ Donald J. Tringali Chairman of the Board of Directors March 16, 2026

Donald J. Tringali

/s/ J. Anthony Gallegos, Jr. Director March 16, 2026

J. Anthony Gallegos, Jr.

/s/ Georganne Hodges Director March 16, 2026

Georganne Hodges

/s/ Nigel J. Jenvey Director March 16, 2026

Nigel J. Jenvey

/s/ Jean K. Holley Director March 16, 2026

Jean K. Holley

/s/ Stephen C. Taylor Director March 16, 2026

Stephen C. Taylor

NATURAL GAS SERVICES GROUP, INC.

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS

Page

Consolidated Balance Sheets as of December 31, 2025 and 2024 F-3

Notes to Consolidated Financial Statements:

1. Description of Business F-7

2. Summary of Significant Accounting Policies F-7

3. Trade Accounts Receivables F-11

4. Inventory F-12

5. Assets Held for Sale and Restructuring Activities F-13

6. Rental Equipment F-13

7. Property and Equipment F-14

9. Supplemental Balance Sheet Disclosures F-16

10. Long-Term Debt F-16

11. Income Taxes F-17

12. Deferred Compensation Plan F-19

13. Commitments and Contingencies F-19

14. Stockholders’ Equity F-19

15. Revenues from Customers F-20

16. Stock-Based and Other Long-Term Incentive Compensations F-21

17. Related Party Transactions F-24

18. Earnings (Loss) per Share F-24

19. Subsequent Events F-25

Report of Independent Registered Public Accounting Firm

To the Shareholders and the Board of Directors of

Natural Gas Services Group, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of Natural Gas Services Group, Inc. (the “Company”) as of December 31, 2025 and 2024, and related consolidated statements of operations, stockholders’ equity, and cash flows for each of the three years in the period ended December 31, 2025, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the consolidated financial position of the Company as of December 31, 2025 and 2024, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2025, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control — Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission in 2013, and our report dated March 16, 2026 expressed an unqualified opinion on the effectiveness of the Company's internal control over financial reporting.

Basis for Opinion

These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on the Company’s consolidated financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matter

Critical audit matters are matters arising from the current period audit of the consolidated financial statements that were communicated or required to be communicated to the audit committee and that (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate. We determined that there are no critical audit matters.

/s/ Ham, Langston & Brezina LLP

Houston, Texas

March 16, 2026

We have served as the Company’s auditor since 2022.

F - 1

Report of Independent Registered Public Accounting Firm

To the Shareholders and the Board of Directors of

Natural Gas Services Group, Inc.

Opinion on the Internal Control over Financial Reporting

We have audited Natural Gas Services Group, Inc.'s (the Company) internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control — Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission in 2013 (“COSO”). In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2025, based on criteria established in Internal Control — Integrated Framework issued by COSO.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated balance sheets as of December 31, 2025 and 2024, and related consolidated statements of operations, stockholders’ equity, and cash flows for each of the three years in the period ended December 31, 2025, and the related notes (collectively referred to as the “consolidated financial statements”) of the Company and our report dated March 16, 2026 expressed an unqualified opinion.

Basis for Opinion

The Company’s management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting in the accompanying “Item 9A, Management’s Report on Internal Control Over Financial Reporting”. Our responsibility is to express an opinion on the Company’s internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audit also included performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control over Financial Reporting

A company's internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company's internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the company's assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Ham, Langston & Brezina LLP

Houston, Texas

March 16, 2026

We have served as the Company’s auditor since 2022.

F - 2

NATURAL GAS SERVICES GROUP, INC.CONSOLIDATED BALANCE SHEETS(in thousands)

December 31,

ASSETS

Current Assets:

Cash and cash equivalents $ — $ 2,142

Trade accounts receivable, net of provision for credit losses 18,497 15,626

Inventory, net of allowance for obsolescence 20,647 18,051

Income taxes receivable and prepayments 14,056 11,282

Assets held for sale 2,227 —

Long-term inventory, net of allowance for obsolescence — —

Rental equipment, net of accumulated depreciation 498,525 415,021

Property and equipment, net of accumulated depreciation 20,519 22,989

LIABILITIES AND STOCKHOLDERS’ EQUITY

Current Liabilities:

Commitments and contingencies (Note 13)

Stockholders’ Equity:

Preferred stock, 5,000 shares authorized, no shares issued or outstanding — —

Total liabilities and stockholders’ equity $ 586,786 $ 492,528

See accompanying notes to these consolidated financial statements.

F - 3

Year Ended December 31,

Revenue:

Cost of revenues (excluding depreciation and amortization):

Retirement of rental equipment 728 28 505

Gain on disposition of assets, net (270) (430) (481)

Other income (expense):

Interest income 2,444 — —

Earnings per share:

Weighted average shares outstanding:

See accompanying notes to these consolidated financial statements.

F - 4

NATURAL GAS SERVICES GROUP, INC.

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY

(in thousands)

Shares Amount Shares Amount Shares Amount

Stock-based compensation — — — 2 2,052 — — — 2,054

Vesting of restricted stock/units — — 169 — — — — — —

Stock-based compensation — — — — 1,821 — — — 1,821

Vesting of restricted stock/units — — 51 1 (1) — — — —

Exercise of common stock options — — 23 — 293 — — — 293

Stock-based compensation — — — — 2,126 — — — 2,126

Exercise of common stock options — — 14 — 168 — — — 168

Dividends declared — — — — — (2,665) — — (2,665)

See accompanying notes to these consolidated financial statements.

F - 5

Year Ended December 31,

CASH FLOWS FROM OPERATING ACTIVITIES:

Retirement of rental equipment 728 28 505

Gain on the disposition of assets, net (270) (430) (481)

(Gain) loss on company owned life insurance (63) (156) 235

Changes in operating assets and liabilities:

Prepaid expenses, income taxes receivable and prepayments (3,395) 152 (7)

CASH FLOWS FROM INVESTING ACTIVITIES:

Purchase of company owned life insurance, net — (22) (422)

Proceeds received from insurance for damages to equipment 96 — —

Proceeds from disposition of assets, net 94 476 477

CASH FLOWS FROM FINANCING ACTIVITIES:

Repayments of credit facility borrowings (11,122) (22,000) —

Payments of other long term liabilities — (780) (95)

Proceeds from exercise of stock options 168 293 —

Payment of dividends (2,637) — —

Taxes paid related to net share settlement of equity awards (6) (178) (983)

NET CHANGE IN CASH AND CASH EQUIVALENTS (2,142) (604) (626)

CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD 2,142 2,746 3,372

CASH AND CASH EQUIVALENTS AT END OF PERIOD $ — $ 2,142 $ 2,746

SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:

Income taxes paid, net of refunds received $ 259 $ — $ —

SUPPLEMENTAL DISCLOSURES OF NON-CASH TRANSACTIONS:

Transfer of rental equipment to inventory $ — $ 51 $ 665

Transfer of right of use assets to property and equipment $ — $ 2,641 $ —

Transfer of property and equipment to assets held for sale $ 2,227 $ — $ —

Accrued purchases of property and equipment $ 1,975 $ 2,687 $ —

Right of use assets acquired through a finance lease $ — $ 2,174 $ 1,146

Right of use assets acquired through an operating lease $ 1,989 $ 563 $ 63

See accompanying notes to these consolidated financial statements.

F - 6

NATURAL GAS SERVICES GROUP INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(in thousands, except per share amounts or where otherwise indicated)

1. Description of Business

Natural Gas Services Group, Inc. (the “Company,” “NGS,” “Natural Gas Services Group,” “we,” “us” or “our”) (a Colorado corporation), is a leading provider of natural gas and electric compression equipment, technology and services to the energy industry. We rent, design, install, service and maintain compressors and related equipment and parts for our customers’ oil and gas production and processing facilities, generally using equipment from OEM suppliers along with limited in-house assembly. We are headquartered in Southlake, Texas, with administrative offices in Midland, Texas, an engineering facility located in Tulsa, Oklahoma, and service facilities located in major oil and gas producing basins in the continental United States (“U.S.”).

2. Summary of Significant Accounting Policies

Principles of Consolidation and Basis of Presentation

The accompanying Consolidated Financial Statements were prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) and the rules and regulations of the Securities and Exchange Commission (the “SEC”) and include the accounts of the Company, its subsidiary, NGSG Properties, LLC and the rabbi trust associated with our deferred compensation plan (see Note 12). All significant intercompany accounts and transactions for the periods presented have been eliminated in consolidation.

Use of Estimates

The preparation of our Consolidated Financial Statements in conformity with GAAP requires our management to make estimates and assumptions that affect the amounts reported in these Consolidated Financial Statements and accompanying notes. Actual results could differ from those estimates. Significant estimates include fixed asset lives, provision for credit losses, the allowance for inventory obsolescence and the determination of carrying values in excess of fair values, when applicable, in connection with our annual review of our long-lived assets for impairment.

Cash and Cash Equivalents

For purposes of reporting cash and cash equivalents and cash flows, we consider all short-term investments with an original maturity of three months or less to be cash equivalents. At times, cash balances at banks and financial institutions may exceed federally insured amounts.

Accounts Receivable and Credit Losses

Our trade accounts receivable are generally for 30 days in accordance with the payment terms specified in our master rental service and similar agreements. Our trade accounts receivable are substantially concentrated with customers in the exploration and production industry and range from large, multinational majors to regional firms of various sizes. We perform ongoing credit evaluations of our customers and adjust credit limits based on management’s assessment of the customer’s financial condition and payment history, as well as industry and general economic conditions. We continuously monitor collections and payments from our customers, and maintain an allowance for estimated credit losses based upon our historical experience and any specific customer collection issues that we have identified as well as forecasts of future economic conditions. While such credit losses have historically been within our expectations and the allowance established, we cannot guarantee that we will continue to experience the same credit loss rates that we have in the past.

F - 7

Revenue Recognition

The following is a description of principal activities from which we generate our revenue and the accounting policies that we apply for the recognition thereof:

Rental Revenue. We generate revenue from renting compressor equipment to our customers for the right to control the use of the equipment ratably over the term of the underlying master rental service and similar agreements. Our agreements for rental equipment qualify as operating leases under the Financial Accounting Standards Board’s (“FASB”) Accounting Standards Codification (“ASC”) Topic 842, Leases, as amended (“ASC 842”), as we retain the primary exposure to changes in the underlying equipment’s value as the lessor unlike a sale or secured lending arrangement. Our agreements may also include a fee for servicing the equipment and surcharges for fluids, including oil, during the term of the underlying rental agreement. We have applied the practical expedient provided in ASC 842, which allows us to combine lease and non-lease components. Our rental agreements typically range from 12 to 60 months.

As a lessor, we recognize operating lease revenue on a straight-line basis with equal monthly payments over the term of the underlying agreements. After the terms of the agreement have expired, a customer may renew their contract or continue renting on a monthly basis thereafter. The leased equipment is generally skid-mounted and can be moved to different locations at the direction of our customers. The leased equipment assets remain on our Consolidated Balance Sheets consistent with other property and equipment. Cash receipts associated with our lease agreements are classified within cash flows from operating activities in our Consolidated Statements of Cash Flows.

Sales and Aftermarket Services Revenue. We generate revenue from the sale of component parts as well as exchange/rebuilding customer owned compressors and sale of used rental equipment. We also provide routine aftermarket or call-out services on customer owned equipment.

Consistent with ASC Topic 606, Revenues from Contracts with Customers, as amended (“ASC 606”), revenue is measured and recognized based on a consideration specified in a customer’s contract, excluding any sale incentives and taxes collected on behalf of third parties (i.e. sales and property taxes). Revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration that we expect to receive for those goods or services. To recognize revenue, we (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when, or as, we satisfy the performance obligation(s). Transaction prices are not subject to variable consideration constraints. Shipping and handling costs incurred are accounted for as fulfillment costs and are included in cost of revenues in our Consolidated Statements of Operations.

For sales, revenue is recognized when control has passed to the customer generally when the equipment is completed and shipped. These contracts also may include an assurance warranty clause to guarantee the product is free from defects in material and workmanship for a set duration of time; this is a standard industry practice and is not considered a performance obligation. The amount of revenue recognized is not adjusted for expected returns, as our historical returns have been de minimis. Revenue for aftermarket and other services is recognized after the services in the contract are rendered.

Inventory Valuation

Inventory (current and long-term) is valued at the lower of cost or net realizable value. The cost of inventories is determined by the weighted average method. We regularly review inventory quantities on hand and record a provision for excess and obsolete inventory based primarily on current and anticipated customer demand and assembly requirements. We routinely review our inventory allowance to account for slow moving or obsolete inventory costs that may not be recoverable in the future. We assess anticipated customer demand based on current and upcoming activities and budgets of our major customers as well as other significant companies in the industry, along with oil and gas price forecasts and other factors affecting the industry. Our long-term inventory, which is fully reserved, consisted of raw materials and replacement parts that remain viable but with limited marketing opportunities.

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Long-Lived Assets

Rental equipment and property and equipment are recorded at cost less accumulated depreciation, except for work-in-progress on new rental equipment which is recorded at cost until completion and addition to our fleet. Depreciation is computed using the straight-line method over the estimated useful lives of the major asset categories as follows:

Rental equipment 15 to 25 years

Buildings and leasehold improvements 5 to 39 years

Machinery, equipment and furniture 5 to 7 years

Computer hardware and software 3 to 5 years

Vehicles 3 years

We assess our rental equipment and property and equipment for impairment whenever events or changes in circumstances indicate that the carrying value may not be recoverable. The following factors could trigger an impairment review: significant underperformance relative to historical or projected future cash flows; significant adverse changes in the extent or manner in which the asset (or asset group) is being used or its condition, including a meaningful drop in fleet utilization over the prior four quarters; significant negative industry or company-specific trends or actions, including meaningful activity and budget reductions by our major customers or other sizable exploration and production or midstream companies, as well as significant declines in oil and gas prices; legislative changes prohibiting us from leasing our compressor units; or poor general economic conditions. An impairment loss is recognized if the future undiscounted cash flows associated with the asset (or asset group) and the estimated fair value of the asset are less than the asset’s carrying value.

Sales of equipment out of the rental fleet are included with sales revenue and cost of sales, while retirements of units are presented as a separate operating expense. Maintenance and repairs are charged to cost of rentals as incurred.

Intangible Assets

We amortize intangible assets with definite lives over their useful lives and review for impairment when indicators of impairment are present. We review indefinite-lived intangible assets for impairment annually or when indicators of impairment are present. We review intangibles through an assessment of the estimated future cash flows related to such assets. In the event that assets are found to be carried at amounts in excess of estimated undiscounted future cash flows, then the assets will be adjusted for impairment to a level commensurate with a discounted cash flow analysis of the underlying assets. As of December 31, 2024, we no longer have any intangible assets. Amortization expense attributable to our former intangible assets was $0.1 million for each of the years ending December 31, 2024 and 2023. We also incurred an impairment charge of $0.7 million for an intangible asset attributable to a trade name during the year ended December 31, 2024.

Leases

We determine if an arrangement is a lease at inception by assessing whether it conveys the right to control the use of an identified asset for a period of time in exchange for consideration. We determine lease classification and recognize right-of-use (“ROU”) assets and liabilities on the lease commencement date based on the present value of lease payments over the lease term. For each lease that (i) contains the same timing and pattern of transfer for lease and non-lease components and (ii) if the lease component, if accounted for separately, would be classified as an operating lease, we have elected the practical expedient to not separate non-lease components from lease components. ROU assets and lease liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. As substantially all of our leases do not provide an implicit rate, we use our incremental borrowing rate, which is based on a fully collateralized loan over the lease term, to determine the present value of lease payments. Our ROU assets are included in Other assets and the related current and long-term lease obligations are included in Accrued liabilities and Other long-term liabilities, respectively, on our Consolidated Balance Sheets.

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Internal-Use Software

We maintain and utilize certain computer software applications that we own to support our business information needs. Such software is capitalized on our Consolidated Balance Sheets within Property and equipment (see Note 7) that is amortized over its useful life and recognized as a component of Depreciation and amortization in our Consolidated Statements of Operations. In addition, certain of our information technology service contracts are considered hosting arrangements. Accordingly, certain qualifying costs associated with the implementation of a hosting arrangement are capitalized on our Consolidated Balance Sheets within Other assets and amortized over the term of the respective contract beginning on the date for each component of the hosting arrangement when the component is ready for its intended use. Amortization of capitalized implementation costs of our hosting arrangements are recognized in our Consolidated Statements of Operations within Selling, general and administrative expenses consistent with the fees for the associated hosting arrangement services.

Income Taxes

Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases, and net operating losses and tax credit carry-forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the period that includes the statutory enactment date. Valuation allowances are established to reduce deferred tax assets when it is more likely than not that some portion or all of the deferred tax assets will not be realized.

With respect to uncertain tax positions, GAAP prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. In order to record any financial statement benefit, we are required to determine, based on technical merits of the position, whether it is more likely than not (a likelihood of more than 50 percent) that a tax position will be sustained upon examination, including resolution of any related appeals or litigation processes. If that step is satisfied, then we must measure the tax position to determine the amount of benefit to recognize in the financial statements. The tax position is measured at the largest amount of the benefit that is greater than 50 percent likely of being realized upon ultimate settlement. We had no liabilities for uncertain tax positions as of December 31, 2025 and 2024.

Our policy regarding income tax interest and penalties is to charge those items as components of interest expense and other income (expense), respectively.

Capitalized Interest

We capitalize interest from external borrowings on significant expenditures for the assembly of our natural gas compressor equipment until such projects are ready for their intended use. Capitalized interest is added to the cost of the underlying asset and is amortized over the useful lives of the assets in the same manner as the underlying assets.

Fair Value Measurement

Fair value 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 under current market conditions. GAAP provides for a fair value hierarchy, which requires an entity to maximize the use of observable inputs when measuring fair value. These inputs are categorized as follows:

Level 1 - quoted prices in an active market for identical assets or liabilities;

Level 2 - quoted prices in an active market for similar assets or liabilities, inputs other than quoted prices that are observable for similar assets or liabilities, inputs derived principally from or corroborated by observable market data by correlation or other means; and

Level 3 - valuation methodology with unobservable inputs that are significant to the fair value measurement.

We believe that the fair value of our cash and cash equivalents, trade accounts receivables, and accounts payable as of December 31, 2025 and 2024 approximate their carrying values due to the short-term nature of the instruments or the use of prevailing market interest rates. We considered the borrowings under our credit facility to approximate fair value based upon variable interest rates currently available to us for loans with similar terms (level 2).

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Segments and Related Information

GAAP defines the characteristics of an operating segment as (i) being engaged in business activity from which it may earn revenue and incur expenses, (ii) being reviewed by the Company’s chief operating decision maker (“CODM”) for decisions about resources to be allocated and assess its performance and (iii) having discrete financial information. Although we review our service and product offerings (rentals, sales and aftermarket services) to analyze the nature of our revenue, costs and expenses, the net income and non-GAAP financial measures including EBITDA and Adjusted gross margin are not captured or analyzed by these categories. Our chief executive officer (“CEO”) serves as the CODM and does not make resource allocation decisions or assess the performance of the business based on these service and product offerings, but rather on the entire entity in the aggregate. Accordingly, the measures of profit and loss and total assets are effectively those of the Company as a whole as reflected in these Consolidated Financial Statements. Based on these facts and underlying circumstances described further below, we have concluded that we operate in one business segment.

We are primarily engaged in the business of leasing natural gas and electric compression equipment to our customers. In addition, we design, sell, install, service and maintain compressors and related equipment and parts. These business activities are similar in all geographic areas in which we operate. Our customers primarily consist of entities in the business of producing oil and gas. The maintenance and service of our products is consistent across the entire Company and is performed by a dedicated group of employees via an internal fleet of vehicles. The regulatory environment is similar in every jurisdiction in that the most impacting regulations and practices are the result of federal energy policy.

Recently Adopted Accounting Pronouncements

In December 2023, the FASB issued Accounting Standards Update (“ASU”) 2023-09 “Income Taxes (Topics 740): Improvements to Income Tax Disclosures” (“ASU 2023-09”) to expand the disclosure requirements for income taxes, specifically related to the rate reconciliation and income taxes paid. We elected to early adopt ASU 2023-09 effective with our financial reporting for the year ended December 31, 2024 and have applied the provisions on a retrospective basis for all periods presented in these Consolidated Financial Statements. Accordingly, the enhanced disclosures required of ASU 2023-09 are provided in Note 11.

In November 2023, the FASB issued ASU 2023-07 “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures” (“ASU 2023-07”) which expands annual and interim disclosure requirements for reportable segments, primarily through enhanced disclosures about significant segment expenses. We adopted ASU 2023-07 effective January 1, 2024 and the required disclosures are referenced above in our discussion of Segments and Related Information.

Recently Issued Accounting Pronouncements Pending Adoption

In November 2024, the FASB issued ASU 2024-03 “Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expense” (“ASU 2024-03”) which expands annual and interim disclosures expenses for certain types of expenses (including purchases of inventory, employee compensation, depreciation, amortization, and depletion) in commonly presented expense captions (such as cost of sales, selling, general & administrative expenses, and research and development). ASU 2024-03 is effective for annual periods beginning January 1, 2027, and for interim periods beginning January 1, 2028, with early adoption permitted. The adoption of ASU 2024-03 is not expected to have a material impact on our Consolidated Financial Statements or disclosures.

3. Trade Accounts Receivable

The following table summarizes our trade accounts receivable from customers as of the dates presented:

December 31,

Trade accounts receivable

Sales and aftermarket services 2,249 2,657

Less: Provision for credit losses (317) (1,249)

Total trade accounts receivable, net $ 18,497 $ 15,626

Our trade accounts receivable consist of customer obligations due under normal trade terms for (i) operating leases for the use of our compressors, (ii) the sale of custom/assembled compressors and parts, as well as exchange/rebuilding customer owned compressors and sale of used rental equipment and (iii) the performance of aftermarket services.

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Major Customers and Concentration of Credit Risk

Rental revenue and sales from Occidental Permian, LTD. (“Oxy”) and Devon Energy Corporation (“Devon”) in 2025, 2024 and 2023amounted to 59 percent, 59 percent and 52 percent of revenue on a combined basis, respectively. No other single customer accounted for more than 10 percent of our revenues in 2025, 2024 and 2023. Oxy’s and Devon’s accounts receivable balances amounted to 62 percent and 60 percent of our accounts receivable as of December 31, 2025 and 2024, respectively. No other customers amounted to more than 10 percent of our accounts receivable on a combined basis as of December 31, 2025 and 2024, respectively.

Provision for Credit Losses

The following table summarizes the changes in our provision for credit losses for the periods presented:

Year Ended December 31,

Management believes that the provision is adequate; however, actual write-offs may exceed the recorded allowance. The substantial write-off of the provision for credit losses during 2025 reflects certain aged receivables that are no longer deemed collectible.

4. Inventory

The following table summarizes the components of our inventory, net of allowances for obsolescence as of the dates presented:

December 31,

Our long-term inventory, which is fully reserved as of December 31, 2025 and 2024, consists of excess raw materials that remain viable but with limited market opportunities.

Allowance for Obsolescence

The following table summarizes the changes in our allowance for obsolescence for the periods presented:

Year Ended December 31,

The allowance for 2023 was primarily related to our decision to cease future compressor assembly at our Midland, Texas facility, which reduced the expected future demand of certain inventory items that were held at this facility. In 2024 and 2025, we continued actions in support of our strategy to further outsource assembly activities to third parties limiting our ability to market certain assembled parts resulting in an additional allowance charges.

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5. Assets Held for Sale and Restructuring Activities

Midland Facility

During the second quarter of 2025, we completed all activities necessary to terminate operations at our facility in Midland, Texas (the “Midland Facility”) and prepared the site, which includes an industrial building and land, for sale. Accordingly, depreciation of the facility was suspended and the combined net carrying value of the building and land, or $2.2 million, was reclassified from property and equipment to an asset held for sale included as a component of current assets on our Consolidated Balance Sheet as of June 30, 2025. We have engaged a broker and are actively marketing the facility. The closure of the Midland Facility was part of our strategy to streamline and outsource our assembly operations and monetize company-owned real estate as disclosed previously. We anticipate that we will complete a sale transaction for the Midland Facility in 2026.

Beginning in the first quarter of 2025, all equipment with continuing productive value was transferred from the Midland Facility to certain of our other regional service centers. By the end of April 2025, the Midland Facility was completely vacant in anticipation of the eventual sale. In addition, we disposed of all inventory items, including engines, frames and coolers, among other items that were fully reserved (see Note 4).

In connection with the complete closure of the Midland Facility, we terminated eight employees and incurred $0.1 million of severance and termination benefits all of which were paid and settled during April 2025.

Other Restructuring Activities

During the year ended December 31, 2024, we incurred and paid an amount less than $0.1 million associated with certain restructuring activities at our assembly facilities for which there were no amounts remaining outstanding.

During the year ended December 31, 2023, we incurred certain restructuring charges in the form of severance and related compensation benefits in connection with a transition in executive leadership. Accordingly, we incurred $1.2 million in severance and related compensation charges in connection with our former CEO for which there were no amounts remaining outstanding with respect to this action.

6. Rental Equipment

The following table summarizes our rental equipment and accumulated depreciation as of the dates presented:

December 31,

Rental equipment, net of accumulated depreciation $ 498,525 $ 415,021

We evaluated our rental equipment for potential impairment as of December 31, 2025 and 2024 and determined that none were present. We capitalized interest totaling approximately $2.5 million, $4.7 million and $5.5 million in connection with the acquisition and assembly of compressor units for the years ended December 31, 2025 and 2024 and 2023, respectively. Depreciation expense for rental equipment was $32.7 million, $28.2 million and $24.0 million for the years ended December 31, 2025, 2024 and 2023, respectively.

Retirement of Rental Equipment

We routinely review our rental fleet for retirement or obsolescence as well as an assessment to determine which units are not of the type, configuration, make or model that our customers are demanding or that are not cost efficient to refurbish, maintain and/or operate. As a result of these reviews, we recorded charges for the retirement of rental equipment of $0.7 million, less than $0.1 million and $0.5 million during the years ended December 31, 2025, 2024 and 2023, respectively.

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Rental Activity

Future minimum rent payments for the periods presented due as of December 31, 2025 from our customers for contractual arrangements, not on a month-to-month basis, were as follows:

Year Ending December 31,

7. Property and Equipment

The following table summarizes our property and non-rental equipment as of the dates presented:

December 31,

Office equipment and furniture 2,099 2,057

Computer hardware and software 619 589

(1) Includes $2.6 million recognized as an impairment in 2025 as discussed below.

In connection with our efforts to plan for an eventual sale of our former corporate headquarters facility including a building and land in Midland, Texas (the “Former Headquarters Property”), we undertook certain actions in the fourth quarter of 2025 to begin building-out a new leased office facility in Midland, Texas.While the Former Headquarters Property remained in use as of December 31, 2025, these actions triggered a review for impairment of the Former Headquarters Property consistent with our plans to relocate to the new leased facility in 2026. In our evaluation for the impairment, the cash flows that we considered were those that we expect to receive from a sale of the Former Headquarters Property, less costs to sell, or fair value. As the carrying value of the Former Headquarters Property exceeded the fair value less costs to sell, we recognized an impairment of $2.6 million in the fourth quarter of 2025. Subsequently, we entered into an exclusive listing agreement in February 2026 for the sale of the Former Headquarters Property (see Note 19).

Depreciation expense for property and equipment was $3.9 million, $2.4 million and $2.4 million for the years ended December 31, 2025, 2024 and 2023, respectively.

During 2025, we reclassified certain items of property and equipment attributable to our former Midland Facility with a carrying value of $2.2 million to assets held for sale (see Note5).

8. Leases

Our operating leases are primarily related to property leases for administrative and field offices, storage facilities, temporary housing and office equipment. Our operating leases have remaining lease terms of one to seven years. Renewal and termination options are included in the lease term when it is reasonably certain that we will exercise the option. Our finance leases were primarily related to vehicles used in our rental business; however, we terminated all such leases during 2024 and purchased the vehicles and recorded them in property and equipment. Prior to their termination, our finance leases generally had lease terms of three years. Our lease agreements do not contain any contingent rental payments, material residual guarantees or material restrictive covenants.

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The following table reflects the amounts related to leases that are recorded on our Consolidated Balance Sheets as of the dates presented:

Classification on Consolidated December 31,

Operating lease assets Other assets $ 2,373 $ 607

Current operating lease liabilities Accrued liabilities $ 462 $ 153

Noncurrent operating lease liabilities Other long-term liabilities 1,911 454

Total lease liabilities $ 2,373 $ 607

Weighted average remaining lease term (in years) 4.9 3.8

Weighted average discount rate 7.4 % 8.3 %

Operating lease costs are recognized on a straight-line basis over the lease term. Total operating lease costs for the years ended December 31, 2025, 2024 and 2023 were approximately $1.0 million,$0.7 million and$0.5 million, respectively.

The following table summarizes the cash paid for amounts included in the measurement of liabilities included in our Consolidated Statements of Cash Flows for the periods presented:

Year Ended December 31,

Finance lease cost (3) $ — $ 622 $ 95

(1)Lease costs are classified in the Consolidated Statements of Operations within cost of revenues and selling, general and administrative expenses.

(2) Includes costs of $0.6 million, $0.1 million and $0.3 million for leases with terms of 12 months or less and $0.4 million, $0.6 million and $0.2 million for leases with terms greater than 12 months for the years ended December 31, 2025, 2024 and 2023, respectively.

(3) All finance leases were terminated during 2024.

The following summarizes the future maturities of our lease liabilities for the periods presented:

Year Ending December 31,

Total lease payments 2,860

Less: Imputed interest (487)

Rent expense under such leases was $0.4 million, $0.6 million and $0.2 million for the years ended December 31, 2025, 2024 and 2023, respectively.

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9. Supplemental Balance Sheet Disclosures

The following table summarizes the components of accrued liabilities as of the dates presented:

December 31

Current operating leases 462 153

10. Long-Term Debt

Our outstanding long-term debt consists of the following as of the dates presented:

December 31,

We have a senior secured revolving credit agreement, as amended (the “Credit Facility”) with Texas Capital Bank, National Association as administrative agent (the “Administrative Agent”), TCBI Securities, Inc., Bank of America, N.A., and the Huntington National Bank as joint lead arrangers and joint book runners, and the lenders party thereto (the “Lenders”). On April 18, 2025, we entered into the Fourth Amendment to the Amended and Restated Credit Agreement (the “Fourth Amendment”) with the Lenders to (i) increase the total commitment to $400.0 million from $300.0 million, (ii) expand the accordion feature to $100.0 million from $50.0 million, (iii) reduce the interest rates by 50 to 75 basis points at comparable leverage levels and, (iv) provide for a more flexible leverage covenant that began on September 30, 2025. In connection with the Fourth Amendment, we incurred fees and debt issue costs of $1.3 million.

The Credit Facility provides for a total commitment of $400.0 million. We also have a right to request from the Lenders, an increase to the potential aggregate commitment of up to $100.0 million; provided, however, the aggregate commitment amount is not permitted to exceed $500.0 million. The accordion feature is subject to certain conditions, including the absence of a default, the consent of new or existing lenders willing to provide additional commitments, and our pro forma compliance with the Credit Facility’s financial covenants. The obligations under the Credit Facility are secured by a first priority lien on most of our assets, including inventory and certain accounts receivable as well as a variable number of our leased compressor units. The maturity date of the Credit Facility is February 28, 2028.

As of December 31, 2025, we had $230.0 million outstanding under our Credit Facility with a weighted average interest rate of 6.59%. As of December 31, 2025, we had approximately $170.0 million available for borrowing under the Credit Facility, subject to borrowing base determination that was determined to be $400.0 million. As of December 31, 2025, we were in compliance with all financial covenants in our Credit Facility.

Borrowing Base. At any time before the maturity of the Credit Facility, we may draw, repay and re-borrow amounts available under the borrowing base up to the maximum aggregate availability discussed above. Generally, the borrowing base equals the sum of (a) 85% of eligible accounts receivable owed to us, plus (b) 50% of the eligible inventory, valued at the lower of cost or market value at such time, subject to a cap of this component not to exceed $2.5 million, plus (c) the lesser of (i) 95% of the net book value of the compressors that the Administrative Agent has determined are eligible for the extension of credit, valued at the lower of cost or market value with depreciation not to exceed 25 years, at such time and (ii) 80% of the net liquidation value percentage of the net book value of the eligible compressors that the Administrative Agent has determined are eligible for the extension of credit, valued at the lower of cost or market value with depreciation not to exceed 25 years, at such time, plus (d) 80% of the net book value, valued at the lower of cost (excluding any costs for capitalized interest or other noncash capitalized costs) or market of the eligible new compressor fleet, minus (e) any required availability reserves determined by the Administrative Agent in its sole discretion. The Administrative Agent may adjust the borrowing base components if material deviations in the collateral are discovered in future audits of the collateral.

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Interest and Fees. Under the terms of the Credit Facility, we have the option of selecting the applicable variable rate for each revolving loan, or portion thereof, of either (a) the Base Rate (as defined below) plus the Applicable Margin, or (b) in the case of a Term Secured Overnight Financing Rate (“SOFR”) Loan, the Adjusted Term SOFR rate plus the Applicable Margin. “Base Rate” means, for any day, a rate of interest per annum equal to the highest of (a) the prime rate for such day; (b) the sum of the federal funds rate for such day plus 0.50%; and (c) the Adjusted Term SOFR for such day plus 1.00%. The Applicable Margin is determined based upon the leverage ratio as set forth in the most recent compliance certificate received by the Administrative Agent for each fiscal quarter from time to time pursuant to the Credit Facility. Depending on the leverage ratio, the Applicable Margin can be 1.50% to 2.25% for Base Rate Loans (as defined in the Credit Facility) and 2.50% to 3.25% for Term SOFR Loans and for requested letters of credit. In addition, we are required to pay a monthly commitment fee on the daily average unused amount of the commitment while the Credit Facility is in effect at an annual rate equal to 0.375% of the unused commitment amount. Accrued interest is payable monthly on outstanding principal amounts and unused commitment fee, provided that accrued interest on Term SOFR Loans is payable at the end of each interest period, but in no event less frequently than quarterly.

Covenants. The Credit Facility contains customary representations and warranties, as well as covenants which, among other things, condition or limit our ability to incur additional indebtedness and liens; enter into transactions with affiliates; make acquisitions in excess of certain amounts; pay dividends; redeem or repurchase capital stock or senior notes; make investments or loans; make negative pledges; consolidate, merge or effect asset sales; or change the nature of our business. In addition, we are subject to certain financial covenants in the Credit Facility that require us to maintain (i) a leverage ratio, as defined, lesser than or equal to (a) 3.50 to 1.00 for each fiscal quarter and (ii) a fixed charge coverage ratio greater than or equal to 1.25 to 1.00 as of the last day of each fiscal quarter.

Events of Default and Acceleration. The Credit Facility contains customary events of default for credit facilities of this size and type, and includes, without limitation, payment defaults; defaults in performance of covenants or other agreements contained in the Credit Facility and the other transaction documents; inaccuracies in representations and warranties; certain defaults, termination events or similar events; certain defaults with respect to any other Company indebtedness in excess of $1.0 million; certain bankruptcy or insolvency events; the rendering of certain judgments in excess of $1.0 million; certain ERISA events; certain change in control events and the defectiveness of any liens. Obligations outstanding under the Credit Facility may be accelerated upon the occurrence of an event of default.

11. Income Taxes

The following table summarizes our provision for income taxes for the presented:

Year Ended December 31,

Current income tax benefit (expense):

Total current income tax benefit (expense) 54 (202) (35)

Deferred income tax (expense) benefit:

The following table summarizes the effective tax rates for the periods presented:

Year Ended December 31,

Stock-based compensation — — % 195 (0.9) % (46) 0.7 %

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The following table summarizes the income tax effects of temporary differences that give rise to significant portions of deferred income tax assets and (liabilities) as of the dates presented:

December 31,

Deferred income tax assets:

Research and development credits 1,026 1,011

Stock-based compensation 132 269

Deferred income tax liabilities:

Total deferred income tax liabilities (84,329) (73,198)

Net deferred income tax liabilities $ (52,530) $ (45,873)

We file income tax returns in the U.S. federal jurisdiction and various state jurisdictions. With few exceptions, we are no longer subject to U.S. federal or state income tax examination by tax authorities for years before 2020.

Income Taxes Receivable

On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (“CARES Act”) was enacted in response to the economic impact caused by the COVID-19 pandemic. The CARES Act, among other things, permits federal income tax net operating loss (“NOL”) carryovers and carrybacks to offset 100% of taxable income for taxable years beginning before 2021. In addition, the CARES Act allows NOLs incurred in 2018, 2019, and 2020 to be carried back to each of the five preceding taxable years to generate a refund of previously paid federal income taxes. We generated significant NOLs during 2018 and 2019 and filed carryback claims for these losses to the preceding five years.

In connection with the filing of these claims, we initially recorded a federal income tax receivable of approximately $15.0 million and certain related adjustments to our deferred tax liability. We subsequently received federal income tax refunds corresponding to the 2018 NOL carryback during 2020 leaving approximately $11.5 million remaining to be refunded in connection with the 2019 NOL carryback. In conjunction with the remaining income tax refund claim, we received a notice from the Internal Revenue Service (“IRS”) on March 8, 2023, stating that our income tax returns for 2015, 2016, 2017 and 2019 were selected for examination. Furthermore, and as is customary for income tax refunds of this magnitude, the IRS was required to review the refund claim and provide a report to the Joint Committee on Taxation of the U.S. Congress (“JCT”). As a result of the submission of the refund claim to the JCT, the IRS completed their review of the income tax returns for 2015, 2016 and 2017. Our request for refund was reviewed and concluded favorably with the JCT concurring with the IRS’s conclusions. Subsequent to a delay due to the federal government shutdown in October 2025, we received a total of $12.3 million in the first quarter of 2026. This amount includes tax refunds of $10.2 million and related interest of $2.1 million for the years 2015, 2016 and 2017. After receipt of these refunds, a total of $1.8 million attributable solely to 2019 remains open including an income tax refund of $1.5 million plus interest of $0.3 million.

Other Income Tax Attributes

As of December 31, 2025, we had NOL carryforwards for federal income tax purposes of $124.2 million, which may be carried forward indefinitely and can offset up to 80% of future taxable income in any given year. Future changes in ownership, as defined by Section 382 of the Internal Revenue Code of 1986, as amended (“IRC”), could limit the amount of NOL carryforwards used in any one year. In general, under Section 382 and 383 of the IRC, a corporation that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change NOLs and certain tax credits, to offset future taxable income and tax. In general, an ownership change occurs if the aggregate stock ownership of certain stockholders changes by more than 50 percentage points over such stockholders’ lowest percentage of ownership during the testing period (generally three years). We also had state NOL carryforwards of $58.5 million with carryforward periods similar to those of our federal NOLs.

We paid a total of $0.3 million during 2025for income taxes, net of refunds received, including $0.1 million to the IRS and $0.1 million to the State of Texas. We have no reserves for uncertain tax positions as of December 31, 2025 and 2024.

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NGS US Equity

NGS · 10-K · period ended 2025-12-31

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

ITEM 9A. CONTROLS AND PROCEDURES

ITEM 9B. OTHER INFORMATION

ITEM 9C. DISCLOSURES REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

ITEM 11. EXECUTIVE COMPENSATION

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTORINDEPENDENCE

ITEM 14. PRINCIPAL ACCOUNTANT FEES AND SERVICES

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

ITEM 16. FORM 10-K SUMMARY

NGS US Equity☆

NGS · 10-K · period ended 2025-12-31

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE

ITEM 9A. CONTROLS AND PROCEDURES

ITEM 9B. OTHER INFORMATION

ITEM 9C. DISCLOSURES REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

ITEM 11. EXECUTIVE COMPENSATION

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTORINDEPENDENCE

ITEM 14. PRINCIPAL ACCOUNTANT FEES AND SERVICES

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

ITEM 16. FORM 10-K SUMMARY

NGS US Equity