A strong lime story hits a demand test
- USLM sells basic but important materials, mainly lime and limestone products, into many industrial and construction markets.
- Fiscal 2025 was very strong: revenue rose 17.3%, helped by an 8.4% volume gain and an 8.2% price gain.
- Q1 2026 broke that streak, with revenue down 3.7% as volumes fell and prices slipped slightly.
- The bull case depends on construction demand coming back and the new Texas kiln starting up well in summer 2026.
- The bear case is that margins have peaked, because fuel and transportation costs rose while pricing power faded.
The pause after a hot year
USLM had a standout 2025. Revenue from lime and limestone products rose 17.3% to $372.7 million. The growth was balanced, with volumes up 8.4% and average prices up 8.2%. Gross profit margin also improved to 48.9% from 45.3%, helped by higher prices, stronger demand, and lower fuel costs.
Q1 2026 changed the tone. Revenue fell 3.7% from the prior year, the first year-over-year revenue decline since the COVID period began in 2020. Volumes fell 3.4%, average prices fell 0.2%, and demand weakened from construction, oil and gas, and roof shingle customers. Steel demand helped, but not enough to keep revenue growing.
The bull case is still alive. Management said it remains optimistic about the rest of the year, especially construction demand. A new Texas kiln is expected to start up in summer 2026, and the project is estimated to cost about $65 million. If that kiln runs well and customers take the new output at good prices, USLM can return to growth.
The bear case is now easier to see. The company moved from strong pricing in 2025 to a small price decline in Q1 2026, while fuel and transportation costs rose. That mix hurt gross profit, which fell 9.5% in the quarter. The open question is whether Q1 was a weather and timing pause, or an early sign that construction demand, including data center work, is cooling.
Quarries, kilns, and local demand
USLM mines limestone and turns it into products that customers use in construction, steelmaking, water treatment, paper, glass, roofing, farming, and oilfield work. It operates plants and distribution facilities in Arkansas, Colorado, Louisiana, Missouri, Oklahoma, and Texas. Most products are shipped by truck or rail within about 400 miles of each plant, so the business is local and regional.
The company makes money by selling tons of material at prices above its mining, kiln, labor, energy, and freight costs. That sounds simple, but small changes in volume, price, fuel, or transportation can move profit a lot. Management says profits are very sensitive to sales volumes, prices, and costs.
Customer concentration looks low at the company level. In 2025, about 675 customers bought lime and limestone products, and no single customer was more than 10% of those sales. The bigger concentration question is not one named customer. It is how much recent growth came from data center construction, which the filings do not break out.
Old materials with hard-to-skip uses
Quicklime
Quicklime is made by heating limestone in kilns. Customers use it in metal processing, flue gas treatment, construction soil stabilization, paper, sanitation, and water treatment.
Hydrated lime
Hydrated lime is made by reacting quicklime with water. It is used in water treatment, soil stabilization, flue gas treatment, asphalt, drilling mud, and chemicals.
Lime slurry
Lime slurry is a water mix of calcium hydroxide. USLM says it is used mainly in soil stabilization for highway, road, and building construction.
Pulverized limestone
Pulverized limestone is ground limestone. It goes into roof shingles, asphalt paving, animal feed, glass, agriculture, flue gas treatment, and mine safety dust.
Crushed limestone
Crushed limestone is sold mainly as a construction aggregate. It is a basic input, so demand can rise and fall with local construction activity.
Natural gas interests
USLM also has royalty and non-operated working interests in natural gas wells in the Barnett Shale in Johnson County, Texas. This is not the core lime business.
Production comes from six mines
USLM reports one main lime and limestone business, but its 2025 filing gives mined limestone tons by property. The mix below uses 2025 mined tons, not revenue, so it does not show customer or data center exposure.
What could crack the margin
Construction slowdown
High impact · Medium oddsConstruction has been a key demand driver, including large data center work in 2025. In Q1 2026, construction demand fell, which helped drive the 3.7% revenue decline. If this is a cycle change rather than a short pause, USLM may have weaker volumes just as new kiln capacity arrives.
Fuel and freight squeeze
High impact · Medium oddsKilns and hauling use energy, trucks, rail, and fuel. In Q1 2026, higher fuel and transportation costs helped push gross profit down 9.5%. If USLM cannot pass those costs into prices, margins can fall quickly.
New Texas kiln ramp risk
Medium impact · Medium oddsThe new Texas kiln is expected to start up in summer 2026 and is estimated to cost about $65 million. A late start, poor early output, or low customer take-up would weaken the growth case. Depreciation also begins when the kiln consistently produces saleable quicklime, which could lift expenses in the second half of 2026.
Pricing power fades
High impact · Medium oddsUSLM had an 8.2% average price increase in 2025, but Q1 2026 showed a 0.2% price decline. That is small, but the change in direction matters. If customers push back while costs rise, the 2025 margin level may be hard to repeat.
Permits and plant interruptions
Medium impact · Low oddsUSLM depends on quarries, mines, kilns, plants, trucks, and rail. Accidents, weather, labor issues, supply delays, utility problems, or permit trouble can stop shipments. Environmental, health, safety, and mine rules also affect how the company expands and runs its sites.
In one breath
What does United States Lime & Minerals do?
USLM makes lime and limestone products. Its materials are used in construction, steel, water treatment, flue gas treatment, roofing, agriculture, paper, glass, and oilfield services.
Why did USLM revenue fall in Q1 2026?
Revenue fell 3.7% because sales volumes dropped 3.4% and average prices slipped 0.2%. The company pointed to weaker demand from construction, oil and gas, and roof shingle customers, partly offset by stronger steel demand.
Why does the Texas kiln matter?
The Texas kiln adds capacity and is expected to start up in summer 2026. It matters because the growth case depends on filling that new capacity at profitable prices, while the risk is that demand or costs disappoint.
Is USLM exposed to data centers?
Yes, the company said 2025 volume growth was helped by construction demand, including large data centers. The filing does not say how much revenue comes from data centers, so that remains an important open question.