UNITED STATES LIME & MINERALS INC (USLM) Business

ITEM 1. BUSINESS.

General.

United States Lime & Minerals, Inc. (the “Company,” the “Registrant,” “We” or “Our”), which was incorporated in 1950, conducts lime and limestone operations.

The Company’s principal corporate office is located at 5429 LBJ Freeway, Suite 230, Dallas, Texas 75240. The Company’s telephone number is (972) 991-8400 and its internet address is www.uslm.com. The Company’s annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), as well as the Company’s definitive proxy statement filed pursuant to Section 14(a) of the Exchange Act, are available free of charge on the Company’s website as soon as reasonably practicable after the Company electronically files such material with, or furnishes it to, the Securities and Exchange Commission (the “SEC”).

Company Operations.

Business and Products. The Company is a manufacturer of lime and limestone products, supplying primarily the construction (including highway, road, and building contractors), industrial (including paper and glass manufacturers), environmental (including municipal sanitation and water treatment facilities and flue gas treatment processes), metals (including steel producers), roof shingle manufacturers, agriculture (including poultry producers), and oil and gas services industries. The Company is headquartered in Dallas, Texas and operates lime and limestone plants and distribution facilities in Arkansas, Colorado, Louisiana, Missouri, Oklahoma and Texas through its wholly owned subsidiaries, Arkansas Lime Company, ART Quarry TRS LLC (DBA Carthage Crushed Limestone), Colorado Lime Company, Mill Creek Dolomite, LLC, Texas Lime Company, U.S. Lime Company, U.S. Lime Company-Shreveport, U.S. Lime Company-St. Clair and U.S. Lime Company-Transportation. In addition, the Company, through its wholly owned subsidiary, U.S. Lime Company-O & G, LLC, has royalty and non-operated working interests in natural gas wells located in Johnson County, Texas, in the Barnett Shale Formation.

The Company produces high-quality limestone from its open-pit quarries and underground mines that it sells as crushed limestone or processes further to produce several higher-value lime and limestone products, including pulverized limestone (“PLS”), quicklime, hydrated lime, and lime slurry. PLS (also referred to as ground calcium carbonate) is produced by applying heat to dry the limestone, which is then ground to granular and finer sizes. Quicklime (calcium oxide) is produced by heating limestone to very high temperatures in kilns in a process called calcination. Hydrated lime (calcium hydroxide) is produced by reacting quicklime with water in a controlled process. Lime slurry (milk of lime) is a suspended solution of calcium hydroxide produced by mixing quicklime with water in a lime slaker.

Crushed limestone is used primarily in construction aggregates. PLS is used in the production of construction materials, such as roof shingles and asphalt paving, as an additive to agriculture feeds, in the production of glass, as an agricultural soil enhancement, in flue gas treatment for utilities and other industries requiring scrubbing of emissions for environmental purposes and for mine safety dust in coal mining operations. Quicklime is used primarily in metal processing, in flue gas treatment, in soil stabilization for highway, road, and building construction, as well as for oilfield roads and drill sites, in the manufacturing of paper products, and in municipal sanitation and water treatment facilities. Hydrated lime is used primarily in municipal sanitation and water treatment facilities, in soil stabilization for highway, road, and building construction, in flue gas treatment, in asphalt as an anti-stripping agent, as a conditioning agent for oil and gas drilling mud, and in the production of chemicals. Lime slurry is used primarily in soil stabilization for highway, road, and building construction.

Product Sales. In 2025, the Company sold almost all of its lime and limestone products in the states of Arkansas, Colorado, Iowa, Kansas, Louisiana, Missouri, Oklahoma, Tennessee, and Texas. Sales were made primarily by the Company’s nine sales employees who call on current and potential customers and solicit orders, which are generally made on a purchase-order basis. The Company also receives orders in response to bids that it prepares and submits to current and potential customers.

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Principal customers for the Company’s lime and limestone products are construction customers (including highway, road, and building contractors), industrial customers (including paper manufacturers and glass manufacturers), environmental customers (including municipal sanitation and water treatment facilities and flue gas treatment processes), metals producers (including steel producers), roof shingle manufacturers, agriculture (including poultry producers), and oil and gas services companies.

Approximately 675 customers accounted for the Company’s sales of lime and limestone products during 2025. No single customer accounted for more than 10% of such sales. The Company is generally not subject to significant customer demand and credit risks as its customers are considerably diversified within its geographic region and by industry concentration. However, given the nature of the lime and limestone industry, the Company’s profits are very sensitive to changes in sales volumes, prices, and costs.

Lime and limestone products are transported by truck and rail to customers generally within a radius of 400 miles of each of the Company’s plants. All of the Company’s 2025 sales were made within the United States.

Seasonality. The Company’s sales have typically reflected seasonal trends, with the largest percentage of total annual shipments and revenues normally being realized in the second and third quarters. Lower seasonal demand normally results in reduced shipments and revenues in the first and fourth quarters. Inclement weather conditions generally have a negative impact on the demand for lime and limestone products supplied to construction-related customers, as well as on the Company’s open-pit quarrying operations.

Limestone Mineral Resources and Reserves. The Company’s limestone mineral resources and reserves contain at least 96% calcium carbonate (CaCO3). The Company has four subsidiaries that extract limestone from open-pit quarries: Texas Lime Company (“Texas Lime”), which operates the Texas Lime Quarry and is located near Cleburne, Texas; Arkansas Lime Company (“Arkansas Lime”), which operates the Batesville Quarry and is located near Batesville, Arkansas; ACT Holdings, Inc. (“ACT”), which owns the Love Hollow Quarry and is located near Cushman, Arkansas; and Mill Creek Dolomite, LLC (“Mill Creek”), which operates the Mill Creek Quarry and is located near Mill Creek, Oklahoma. U.S. Lime Company-St. Clair (“St. Clair”) extracts limestone from the St. Clair Mine, an underground mine located near Marble City, Oklahoma. Carthage Crushed Limestone (“Carthage”) extracts limestone from the Carthage Mine, an underground mine located in Carthage, Missouri. Colorado Lime Company (“Colorado Lime”) owns property containing limestone deposits at Monarch Pass, Colorado. Existing crushed limestone stockpiles on the property are being used to provide feedstock to the Company’s plant in Delta, Colorado. Access to all properties is provided by paved roads and, in the case of Arkansas Lime, St. Clair, Carthage, and Mill Creek, also by rail.

The following table shows annual mined tons of limestone (in thousands) at the Company’s mining properties for the years ended December 31, 2025, 2024, and 2023:

During 2023, the Company engaged SYB Group, LLC (“SYB”) to serve as the Qualified Person (“QP”) to update estimates of the Company’s limestone mineral resources and reserves, as of December 31, 2023, at its quarries and mines at Texas Lime, Batesville, Love Hollow, and St. Clair (collectively, the “Material Properties”) and provide Technical Report Summaries (“TRSs”) to file as Exhibits 96.1-96.4 to its Report on its Form 10-K for the year ended December 31, 2023. The QP was not retained to prepare estimates at Carthage, Mill Creek, or Colorado because the Company had not completed a drilling program sufficient to enable the QP to prepare estimates of the limestone mineral resources and reserves at those properties.

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The Company has not conducted a drilling program on any of the Material Properties subsequent to the December 31, 2023 effective date of the 2023 TRSs. In the 2023 TRSs, limestone resources and reserves were calculated using a $12.70 per ton price assumption for crushed limestone based on the U.S. Geological Survey Mineral Commodity Summaries 2023. The U.S. Geological Survey Mineral Commodity Summaries 2025 increased the price for crushed limestone to $15.86 per ton, but the QP has determined that this change in price did not have a material impact on the calculation of the reserves and resources and that all material assumptions and information from the TRSs for Material Properties as of December 31, 2023 remain current as of December 31, 2025. The Company has not asked the QP to produce updated TRSs as of December 31, 2025, and it has continued to present limestone and mineral resources and reserves for all Material Properties using the 2023 $12.70 per ton price assumption for crushed limestone.

Summaries of the Company’s total limestone mineral resources and reserves for all Material Properties as of December 31, 2025 and 2024 are shown below. The terms Mineral Resource, Measured Resources, Indicated Resources, Mineral Reserves, Proven Reserves, and Probable Reserves are defined in accordance with SEC Regulation S-K subpart 229.1300 governing disclosures by registrants engaged in mining operations. Limestone mineral resources are presented exclusive of limestone mineral reserves.

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Set forth below is a description of each of the Company’s limestone mining properties. The Company considers the four mining properties associated with Texas Lime, Batesville, Love Hollow, and St. Clair to be material for purposes of application of SEC Regulation S-K subpart 229.1300. Included in the description of each of these four Material Properties are disclosures with respect to such property’s limestone mineral resources and reserves. For additional information with respect to the Material Properties, see the TRSs prepared by SYB, as of December 31, 2023, in Exhibits 96.1-96.4 to this Report on Form 10-K.

Texas Lime owns the Texas Lime Quarry and has crushed limestone, PLS, quicklime, and hydrated lime production facilities, located on approximately 5,200 acres of land in Johnson County, Texas that contains known high-quality limestone mineral resources in a bed averaging 25 to 35 feet in thickness. As of December 31, 2025, the total net book value of the Texas Lime Quarry was $13.4 million. As of December 31, 2025, the Texas Lime Quarry had

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56.7 million tons of proven limestone mineral reserves and 47.5 million tons of probable limestone mineral reserves. Based on the current level of production and recovery rates, the Company estimates that these reserves are sufficient to sustain its limestone operations for approximately 70 years.

The following is a map of the Texas Lime Quarry location:

The tables below summarize the limestone mineral resources and reserves at the Texas Lime Quarry as of December 31, 2025 and 2024:

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Arkansas Lime owns the Batesville Quarry and has crushed limestone, PLS, quicklime, and hydrated lime production facilities, located on approximately 1,260 acres of land in Independence County, Arkansas that contains known high-quality limestone mineral resources in a bed averaging 60 feet in thickness. As of December 31, 2025, the Batesville Quarry had a net book value of $4.4 million. As of December 31, 2025, the Batesville Quarry had 8.1 million tons of indicated limestone mineral resources, 6.8 million tons of proven limestone mineral reserves, and 2.9 million tons of probable limestone mineral reserves. Based on the projected level of production and recovery rates, the Company estimates that these reserves are sufficient to sustain its limestone operations for approximately 17 years.

The following is a map of the Batesville Quarry location:

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The tables below summarize the limestone mineral resources and reserves at the Batesville Quarry as of December 31, 2025 and 2024:

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(1) Mining recovery is listed as open-pit/underground recovery.

In 2005, the Company acquired the Love Hollow Quarry, which is owned by ACT and associated with Arkansas Lime, located on approximately 2,500 acres of land in Izard County, Arkansas. In 2022, the Company improved and developed the transportation infrastructure between the Love Hollow Quarry and Arkansas Lime’s production facilities, incurred other development costs to prepare the Love Hollow Quarry for mining, and began sourcing a portion of the Arkansas Lime plant’s limestone requirements from the Love Hollow Quarry. As of December 31, 2025, the Love Hollow Quarry had a net book value of $7.6 million. As of December 31, 2025, the Love Hollow Quarry had 10.4 million tons of measured limestone mineral resources, 66.8 million tons of proven limestone mineral reserves, and 21.0 million tons of probable limestone mineral reserves. Based on the current level of production and recovery rates, the Company estimates that these reserves are sufficient to sustain its limestone operations for more than 80 years.

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The following is a map of the Love Hollow Quarry location:

The tables below summarize the limestone mineral resources and reserves at the Love Hollow Quarry as of December 31, 2025 and 2024:

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(1) Mining recovery is listed as open-pit/underground recovery.

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St. Clair operates the St. Clair Mine and has crushed limestone, PLS, quicklime, and hydrated lime production facilities located on approximately 1,400 acres that it owns in Sequoyah County, Oklahoma containing high-quality limestone resources and also has long-term mineral leases that provide the right to mine high-quality limestone resources contained in approximately 1,340 adjacent acres. As of December 31, 2025, the St. Clair Mine had a net book value of $6.9 million. As of December 31, 2025, the St. Clair Mine had 7.8 million tons of measured limestone mineral resources, 129.7 million tons of indicated limestone mineral resources, and 21.3 million tons of proven limestone mineral reserves. Based on the current levels of production and recovery rates, the Company estimates that these reserves are sufficient to sustain its limestone operations for approximately 37 years.

The following is a map of the St. Clair Mine location:

The tables below summarize the limestone mineral resources and reserves at the St. Clair Mine as of December 31, 2025 and 2024:

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Carthage operates the Carthage Mine and has crushed limestone production facilities located on approximately 800 acres that it owns containing high-quality limestone. In addition, Carthage has the right to mine the high-quality limestone contained in approximately 760 adjacent acres pursuant to long-term mineral leases.

Mill Creek operates the Mill Creek Quarry and production facilities located on approximately 570 acres that it owns where it mines and processes crushed dolomitic limestone.

Colorado Lime acquired the Monarch Pass Quarry in November 1995 and has not carried out any mining on the property. The Monarch Pass Quarry, which had been operated for many years until the early 1990s, contains a mixture of limestone types, including high-quality calcium limestone.

Internal Controls Over Limestone Mineral Resources and Reserves Estimates. Internal control procedures followed by the Company’s Quality Control/Quality Assurance Laboratories (“QC/QA Lab”) and its contract geologists when assessing properties for limestone mineral resources and reserves estimates are clearly defined. When undertaken, core drilling is conducted under the direct supervision of the geologists, and all core data is logged using a standard protocol. The geologists are responsible for examining the core and compiling an interval list for X-Ray Florescence (“XRF”) analysis. Splits of cores are bagged and labeled with the depth interval to be analyzed, with the remaining split boxed and stored for reference. Bagged intervals are submitted to the Company’s certified QC/QA Lab for XRF analysis, with any samples not destroyed by the testing process retained at the Company’s core storage facility. On an ongoing basis, the QC/QA Lab analyzes production samples for cutoff grade consistency with expectations used in the estimates for limestone mineral resources and reserves.

When classifying limestone mineral resources and reserves, the Company’s contract geologists apply a fixed cutoff grade and set parameters of geologic confidence to classify the respective resources and reserves. Company management reviews the geologists’ assessments for reasonableness.

Quarrying and Mining. The Company extracts limestone by the open-pit method at its Texas, Batesville, Love Hollow, and Mill Creek Quarries. The Monarch Pass Quarry is also an open-pit quarry but is not being mined at this time. The open-pit method consists of removing any overburden comprising soil and other substances, including inferior limestone, and then extracting the exposed high-quality limestone. The Company removes such overburden by utilizing both its own employees and equipment and those of outside contractors. Open-pit mining is generally less expensive than underground mining. The principal disadvantage of the open-pit method is that operations are subject to inclement weather and overburden removal. The limestone is extracted by drilling and blasting, utilizing standard mining equipment. At the St. Clair and Carthage mines, the Company mines limestone underground using room and pillar mining. The Company has no knowledge of any recent changes in the physical quarrying or mining conditions on any of our properties that have materially affected quarrying or mining operations.

Plants and Facilities. After extraction, the limestone is further crushed and screened to produce crushed limestone, and, in the case of PLS, ground and dried, or, in the case of quicklime, processed in kilns. Quicklime may then be further processed in hydrators and slakers to produce hydrated lime and lime slurry. The Company produces and distributes crushed limestone, PLS, and quicklime products at five plants, six lime slurry facilities, and three terminal facilities. All of its plants and facilities are accessible by paved roads, and, in the case of the Arkansas Lime, St. Clair, and Carthage plants, the Love Hollow Quarry, and the terminal facilities, also by rail.

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In addition to the Company’s production of crushed limestone at each of its plants, the following Company plants produce additional lime and limestone products:

The Texas Lime plant has an annual capacity of approximately 500 thousand tons of quicklime from two preheater rotary kilns. The plant also has PLS equipment, which, depending on the product mix, has the capacity to produce approximately 800 thousand tons of PLS annually. In 2024, the Company began construction of a new vertical kiln at the Texas Lime plant. The Company estimates that the construction costs of the new kiln and related equipment and infrastructure project will total approximately $65 million. Through December 2025, the Company has paid $37.3 million on the Texas kiln project.

The Arkansas Lime plant is situated at the Batesville Quarry. Utilizing three preheater rotary kilns, this plant has an annual capacity of approximately 650 thousand tons of quicklime. The Arkansas Lime plant is approximately 21 miles from the Love Hollow Quarry, to which it is connected by railroad. Arkansas Lime’s PLS and hydrating facilities are situated on a tract of 290 acres located approximately two miles from the Batesville Quarry, to which it is connected by a Company-owned railroad. The PLS equipment, depending on the product mix, has the capacity to produce approximately 300 thousand tons of PLS annually.

The St. Clair plant has an annual capacity of approximately 250 thousand tons of quicklime from one vertical kiln and one preheater rotary kiln. The plant also has PLS equipment, which has the capacity to produce approximately 150 thousand tons of PLS annually.

The Carthage plant has facilities located next to the Carthage Mine that produce both crushed limestone and PLS. The equipment has the capacity to produce approximately 900 thousand tons annually.

The Mill Creek plant has facilities located next to the Mill Creek Quarry that produce dolomitic PLS products. The equipment has the capacity to produce approximately 300 thousand tons annually.

The Company also maintains lime hydrating and bagging equipment at the Texas, Arkansas, and St. Clair plants. Storage facilities for lime and limestone products at each plant consist primarily of cylindrical tanks, which are considered by the Company to be adequate to protect its lime and limestone products and to provide an available supply for customers’ needs at the expected volumes of shipments. Equipment is maintained at each plant to load trucks and, at the Arkansas Lime, St. Clair, and Mill Creek plants, to load railroad cars.

Colorado Lime operates a limestone grinding and bagging facility with an annual capacity of approximately 125 thousand tons, located on approximately three and one-half acres of land in Delta, Colorado.

During 2025, the Company’s utilization rate was approximately 80% of its total annual production capacity for its lime and limestone.

U.S. Lime Company uses quicklime to produce lime slurry, and has four Houston area facilities, including two distribution terminals connected to railroads, to serve the Greater Houston area construction market and four facilities to serve the Dallas-Ft. Worth Metroplex. The Company established U.S. Lime Company-Transportation to deliver the Company’s products to some of its customers and facilities, primarily in Texas.

U.S. Lime Company-Shreveport operates a distribution terminal in Shreveport, Louisiana, which is connected to a railroad, to provide lime storage, hydrating, slurrying, and distribution capacity to service markets in Louisiana and East Texas.

The Company believes that its plants and facilities are adequately maintained and insured.

Human Capital Resources. The Company is committed to attracting and retaining the best and brightest talent to meet the current and future needs of its business. Attracting, retaining, motivating, and investing in the development of human capital resources is a critical part of the Company’s commitment to social, environmental, governance, and sustainability issues.

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At December 31, 2025, the Company employed 346 persons, 110 of whom were represented by unions. The Company is a party to three collective bargaining agreements. The collective bargaining agreement for the Texas facilities expires in November 2026. The collective bargaining agreement for the Carthage facilities expires in May 2028. The collective bargaining agreement for the Arkansas facilities expires in January 2029. Overall, the Company believes that its employee relations are generally good.

Employee Retention and Incentivization. On August 1, 2024, the Company entered into an employment agreement with Timothy W. Byrne, its President and Chief Executive Officer (“CEO”), amending and restating Mr. Byrne’s employment agreement that was dated as of January 1, 2020, with such amendment and restatement effective as of January 1, 2025, and also providing that certain amendments were effective earlier, on August 1, 2024. As a result of the amendment and restatement, Mr. Byrne’s employment agreement was extended until December 31, 2028, and will continue thereafter for successive one-year periods unless the Company or Mr. Byrne gives at least one year’s prior written notice of intent not to renew. Under the employment agreement, in addition to the possibility of a discretionary cash bonus, Mr. Byrne is entitled each year to an EBITDA cash bonus opportunity under the United States Lime & Minerals, Inc. 2001 Long-Term Incentive Plan, as Amended and Restated (the “Plan”), and he is also entitled to grants of restricted stock under the Plan.

Mr. Byrne’s employment agreement provides that Mr. Byrne is subject to certain compensation recovery and share ownership provisions designed to align Mr. Byrne’s financial interests with those of the Company’s long-term stockholders, and to ensure that he is incentivized not to take actions that may benefit the Company and its stockholders in the short-term at the expense of long-term corporate value creation and sustainability. In particular, in entering into the employment agreement with Mr. Byrne, the Company’s Board of Directors and Compensation Committee were sensitive to how Mr. Byrne’s leadership and actions could further the Company’s various objectives, including human capital resources development and executive succession planning.

With respect to the Company’s broader employee base, certain employees are eligible to receive annual cash bonuses based on discretionary determinations. Except in the case of Mr. Byrne, the Company has not adopted a formal or informal annual bonus arrangement with pre-set performance goals. Rather, the determination to pay a cash bonus, if any, is made in December each year based on the past performance of the individual and the Company or on the attainment of non-quantified performance goals during the year. In either such case, the discretionary bonus may be based on the specific accomplishments of the individual and/or on the overall performance of the Company. The amounts of the discretionary bonuses for 2025 were based on each employee’s individual performance and accomplishments, as well as those of the Company, including productivity, sales, controlling costs, and contributions made to special projects.

In addition to cash bonuses, the Company makes equity awards to certain individuals under the Plan. The Company uses equity awards granted under the Plan as a means to attract, retain, and motivate the Company’s directors, officers, employees, and consultants. The Company views the use of equity awards under the Plan as an important means of aligning the interests of key individuals with those of its stockholders.

Employee Health and Safety. The Company believes that it is responsible to its employees to provide a safe and healthy workplace environment. The Company seeks to accomplish this by: training employees in safe work practices; openly communicating with employees; following safety standards and establishing and improving safe work practices; involving employees in safety processes; and recording, reporting, and investigating accidents, incidents, and losses to avoid reoccurrence.

Employee Development and Training. The Company encourages and supports the growth and development of its employees. It advances continual learning and career development through ongoing performance and development conversations or evaluations with employees and internally and externally developed training programs. The Company also provides reimbursement for certain educational programs relating to the Company’s business.

Equal Employment Opportunities. The Company is committed to providing equal access to, and participation in, equal employment opportunities, programs, and services, without regard to a person’s gender, nationality, race, and ethnicity. The Company is focused on the development and fair treatment of its employees, including equal employment hiring practices and policies, anti-harassment, and anti-retaliation policies.

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Competition. The lime industry is highly regionalized and competitive, with price, quality, ability to meet customer demands and specifications, proximity to customers, personal relationships, and timeliness of deliveries being the prime competitive factors. The Company’s competitors are predominantly private companies.

The lime industry is characterized by high barriers to entry, including: the scarcity of high-quality limestone deposits on which the required zoning and permitting for extraction can be obtained; the need for lime plants and facilities to be located close to markets, paved roads, and railroad networks to enable cost-effective production and distribution; clean air and anti-pollution regulations, which may make it difficult to obtain permitting for new sources of emissions, such as lime kilns; and the high capital cost of the plants and facilities. These considerations reinforce the premium value of operations having permitted, long-term, high-quality limestone resources and good locations and transportation relative to markets.

Lime producers tend to be concentrated on known high-quality limestone formations where competition takes place principally on a regional basis. While the steel industry and environmental-related users are the largest market sectors, the lime industry also counts chemical users and other industrial users, including paper manufacturers, oil and gas services and highway, road, and building contractors, among its major customers.

In recent years, the lime industry has experienced reduced demand from certain industries as they have experienced cyclical or secular downturns. For example, demand from the Company’s oil and gas services customers has tended to vary with the demand for their products and services, which has continued to be cyclical. In addition, the long-term trend has been for utility plants to use more natural gas and renewable energy sources for power generation instead of coal, with the addition of new coal-fired utility plants in the United States being unlikely, which has reduced their demand for lime and limestone for flue gas treatment processes. These reductions in demand have resulted in increased competitive pressures, including pricing and competition for certain customer accounts, in the industry.

Consolidation in the lime industry has left the three largest companies accounting for more than two-thirds of North American production capacity. In addition to the consolidations, and often in conjunction with them, many lime producers have undergone modernization and expansion and development projects to upgrade their processing equipment in an effort to improve operating efficiency. The Company believes that its modernization, expansion, and development projects in Texas, Arkansas, and Oklahoma, its acquisitions in Oklahoma and Missouri, and its lime slurry operations in Texas, should allow it to continue to remain competitive, protect its markets and position itself for the future. In addition, the Company will continue to evaluate internal and external opportunities for expansion, growth, and increased profitability as conditions warrant or opportunities arise. The Company may revise its strategy or otherwise consider ways to enhance the value of the Company, including by entering into strategic partnerships, mergers, or other transactions.

Compliance with Government Regulations. The Company is subject to various federal, state, and local laws and regulations that may materially impact the Company’s financial condition, results of operations, cash flows, and competitive position. These include laws and regulations relating to the environment, zoning and land use, mine permitting and operations, mine safety, and reclamation and remediation.

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Environmental Laws. The Company owns or controls large areas of land on which it operates limestone quarries, two underground mines, lime plants, and other facilities with inherent environmental responsibilities, compliance costs, and liabilities. These include maintenance and operating costs for pollution control equipment, the cost of ongoing monitoring and reporting programs, the cost of reclamation efforts, and other similar environmental costs and liabilities.

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The Company’s operations are currently subject to various federal, state, and local laws and regulations relating to the environment, health and safety, and other regulatory matters, including the Clean Air Act, the Clean Water Act, the Resource Conservation and Recovery Act, the Emergency Planning and Community Right-to-Know Act, the Comprehensive Environmental Response, Compensation and Liability Act, and analogous state and local laws, including state mining and reclamation statutes and regulations (collectively, “Environmental Laws”). These Environmental Laws have historically granted the United States Environmental Protection Agency (the “EPA”), state governmental agencies, and local governments the authority to promulgate and enforce regulations that could result in substantial expenditures on pollution control, waste management, permitting compliance activities, and mining reclamation. Many

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Environmental Laws also authorize private citizens and interest groups to file lawsuits in court to enforce alleged violations. Changes in policy or political leadership may affect how Environmental Laws are interpreted or enforced by the EPA and state governmental agencies. The failure to comply with Environmental Laws may result in administrative and civil penalties, injunctive relief, and criminal prosecution. The Company has not been named as a potentially responsible party in any federal Superfund cleanup site or state-led cleanup site.

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We are currently entering into a period of uncertainty and rapid change in regard to Environmental Laws and their enforcement. For example, in February 2026, the EPA finalized a rule that eliminates a substantial portion of the greenhouse gas reporting program, including the provisions applicable to the Company’s operations. The new EPA rule immediately triggered legal action from a coalition of state attorneys general and environmental groups. It is uncertain whether the EPA rule will survive judicial review. Changes to Environmental Laws and their enforcement continue to be rapid and turbulent, and the resulting uncertainty can result in significant costs. Permits and other authorizations under Environmental Laws are still required for the Company’s operations, and such permits are subject to modification during the permit renewal process and, in very rare instances, could be revoked.

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Currently, the Clean Air Act and analogous state laws require the Company to obtain authorization to construct or modify existing facilities, and its lime plants are subject to operating permits that have significant ongoing compliance costs. Over time, the EPA has increased the stringency of the National Ambient Air Quality Standards (“NAAQS”), which are used to establish air emission permitting limits under the Clean Air Act. The EPA has lowered ozone standards and reclassified nonattainment areas where State Implementation Plans (“SIPs”) exist. In 2015, the EPA issued a rule establishing the ground-level ozone NAAQS at 70 parts per billion. In 2024, the EPA redesignated the Dallas-Fort Worth nonattainment area, which includes the Texas Lime facility, as a severe nonattainment area under the 2008 ozone standard and a serious nonattainment area under the 2015 ozone standard. The EPA has set attainment dates of August 2027 for the 2008 ozone standard and July 2027 for the 2015 ozone standard. Texas is developing regulations in response to the redesignations to reduce nitrogen oxide and volatile organic compound emissions, which will likely involve more stringent permitting requirements for stationary sources.

In February 2024, the EPA issued a final rule reducing the NAAQS for fine particulate matter. This regulation will significantly increase the number of nonattainment areas across the United States, potentially including areas where the Company operates. States with delegated permitting authority under the Clean Air Act will be required to revise their SIPs accordingly, potentially resulting in more stringent permitting requirements.

In July 2024, under Section 112 of the Clean Air Act, the EPA finalized amendments to the National Emission Standards for Hazardous Air Pollutants (“NESHAPs”) for lime plants. The amended standards must meet the maximum achievable control technology (“MACT”) at major sources of hazardous air pollutants within the lime industry. The revised MACT rule establishes stringent emission limitations for additional hazardous air pollutants which require additional pollution control equipment at lime kilns subject to the rule. The Company’s current operations are not subject to the NESHAP rules due to existing emissions being under the target threshold.

EPA regulations currently require large emitters of greenhouse gases, including the Company’s plants, to collect and report greenhouse gas emissions data. The EPA has previously indicated that it will use the data collected through the greenhouse gas reporting rules to decide whether to promulgate future greenhouse gas emission limits. The EPA and delegated states also regulate greenhouse gas emissions under the New Source Review permitting and Federal Operating Permit programs for facilities that are otherwise subject to permitting based on their emissions of conventional, non-greenhouse gas pollutants. Thus, any new facilities or major modifications to existing facilities that exceed the federal New Source Review emission thresholds for conventional pollutants may be required to use best available control technology and energy efficiency measures to minimize greenhouse gas emissions.

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Although the timing and impact of climate change legislation and of regulations regarding greenhouse gas emissions are uncertain, the consequences of such legislation and regulation are potentially significant for the Company because the production of CO2 is inherent in the manufacture of lime through the calcination of limestone and combustion of fossil fuels. Future greenhouse gas rulemakings could affect New Source Review permitting or other permitting programs and, thereby, increase the time and costs of plant upgrades and expansions. The passage of climate change legislation, and other regulatory initiatives by the Congress, the states, or the EPA that restrict or tax emissions of greenhouse gases, could adversely affect the Company. There is no assurance that changes in the law or regulations will

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not be adopted, such as the imposition of greenhouse gas emission limits, a carbon tax, a cap-and-trade program requiring the Company to purchase carbon credits, or other measures that would require reductions in emissions or changes to raw materials, fuel use, or production rates. Such changes, if adopted, could have a material adverse effect on the Company’s financial condition, results of operations, cash flows, and competitive position.

These and similar rulemakings could increase the cost of future plant modernization, expansion, or development projects, may make it difficult or impossible to obtain new authorizations and permits for new facilities, may require the Company to purchase emissions offsets as a condition of new authorizations and permits, and may increase compliance costs and have a material adverse effect on the Company’s financial condition, results of operations, cash flows, and competitive position.

In addition to regulatory measures, court cases have been filed and decisions issued that may increase the risk of claims being filed by third parties against companies for their greenhouse gas emissions. Such cases may seek to challenge air permits, to force reductions in greenhouse gas emissions, or to recover damages for alleged climate change impacts.

The Company also holds permits for process water and storm water discharges and must comply with the Clean Water Act and analogous state laws and regulations. Any failure to comply with these permits could result in fines or other penalties. Material changes to the terms of these permits or changes to regulations affecting water discharges in the future could also increase compliance costs.

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The manufacturing of quicklime and hydrated lime requires significant volumes of water. The Company operates multiple groundwater wells to provide water to its plants. Groundwater pumping is subject to increased regulation, and in some areas the Company must obtain permits from groundwater conservation districts to pump groundwater. Any failure to comply with these permits could result in fines or other penalties, and future changes that restrict the quantities of groundwater that may be pumped may limit production and increase compliance costs.

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The Company incurred capital expenditures related to environmental matters of $1.6 million, $1.0 million, and $1.5 million in 2025, 2024, and 2023, respectively. The Company’s recurring costs associated with managing environmental permitting and waste recycling and disposal (e.g., used oil and lubricants) and maintaining pollution control equipment amounted to $0.7 million, $0.8 million, and $0.9 million in 2025, 2024, and 2023, respectively.

Mine Safety. The Company’s mining operations are also subject to regulation under the Federal Mine Safety and Health Act of 1977 (the “Mine Act”). The Mine Act has been construed as authorizing the Mine Safety and Health Administration (“MSHA”) to issue citations and orders pursuant to the legal doctrine of strict liability, or liability without fault. If, in the opinion of an MSHA inspector, a condition that violates the Mine Act or regulations promulgated pursuant to it exists, then a citation or order will be issued regardless of whether the operator had any knowledge of, or fault in, the existence of that condition. Many of the Mine Act standards include one or more subjective elements, so that issuance of a citation or order often depends on the opinions or experience of the MSHA inspector involved and the frequency and severity of citations and orders will vary from inspector to inspector.

Whenever MSHA believes that a violation of the Mine Act, any health or safety standard, or any regulation has occurred, it may issue a citation or order which describes the violation and fixes a time within which the operator must abate the violation. In some situations, such as when MSHA believes that conditions pose a hazard to miners, MSHA may issue an order requiring cessation of operations, or removal of miners from the area of the mine, affected by the condition until the hazards are corrected. Whenever MSHA issues a citation or order, it has authority to propose a civil penalty or fine, as a result of the violation, that the operator is ordered to pay.

Citations and orders can be contested before the Federal Mine Safety and Health Review Commission (the “Commission”), and as part of that process, are often reduced in severity and amount, and are sometimes vacated. The Commission is an independent adjudicative agency that provides administrative trial and appellate review of legal disputes arising under the Mine Act. These cases may involve, among other questions, challenges by operators to citations, orders, and penalties that they have received from MSHA, or complaints of discrimination by miners under section 105 of the Mine Act.

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For further information, see Exhibit 95.1 to this Report on Form 10-K.

Reclamation and Remediation. The Company recognizes legal reclamation and remediation obligations associated with the retirement of long-lived assets at their fair value at the time the obligations are incurred (“Asset Retirement Obligations” or “AROs”). Some of the states the Company operates in have reclamation regulations to ensure the proper reclamation of surface mines. These regulations require permitting with the respective state to ensure reclamation obligations are met. Over time, the liability for AROs is recorded at its present value each period through accretion expense, and the capitalized cost is amortized over the useful life of the related asset. Upon settlement of the liability, the Company either settles the ARO for its recorded amount or recognizes a gain or loss. AROs are estimated based on studies and the Company’s process knowledge and estimates and are discounted using an appropriate interest rate. The AROs are adjusted when further information warrants an adjustment. The Company believes its accrual of $1.4 million for AROs at December 31, 2025 is reasonable.

Map of United States Lime & Minerals, Inc. Lime and Limestone Operations.

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