MLM vs USLM: Which Is the Better Buy in 2026?

Same yardstick, side by side (as of October 2026). Valuation lined up like this is most meaningful for two names in the same corner of the market, which these are. Figures are approximate; verify before investing.

Reading it: USLM is the cheaper of the two on forward earnings, but cheaper is not the same as better. Pair the valuation with growth (how far the forward P/E sits below the trailing P/E) and risk (beta) before you decide.

The metrics above tell you which is the marginally better business. The bigger risk for most people is not picking the slightly worse stock, it is over-concentrating. MLM and USLM share themes, so owning both, or adding either to what you already hold, can quietly push a large share of your portfolio into one bet.

This is the part a generic comparison page cannot answer, because it depends on what you own. Connect your brokerage and Walnut shows your real, combined MLM and USLM exposure, flags overlap with your existing positions, and tells you if adding one would tip you past a concentration you are comfortable with, read-only by default, with your login staying at your broker. Walnut is not an investment adviser.

Martin Marietta Materials is the second-largest construction aggregates producer in the United States, behind Vulcan Materials. The aggregates business model is identical to Vulcan: heavy aggregates products with high transport costs create local pricing power within each quarry's service area. Martin Marietta operates hundreds of aggregates facilities across the US with concentration in Texas, Colorado, the Carolinas and other high-growth states, and 2026 added quarries in Virginia, Missouri, Kansas, British Columbia, Minnesota and along the I-70 corridor.

Full MLM guide

United States Lime & Minerals (USLM) is a Dallas, Texas based producer of lime and limestone products, mining high-calcium and dolomitic limestone at its own quarries and processing it into crushed and pulverized limestone, aggregate, quicklime, hydrated lime, and lime slurry. Its plants sit mainly in Texas, Arkansas, Oklahoma, Louisiana, and Colorado, giving it a defensible position in the south-central United States. End markets span steel manufacturing, construction (highways, roads, and buildings), municipal water and wastewater treatment, environmental and flue gas treatment, oil and gas services, roof shingle manufacturing, and agriculture. Because lime is heavy and costly to ship, quarries near their customers enjoy a natural regional moat.

Full USLM guide

Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.

• MLM drivers: Federal infrastructure tailwind; Lime and specialty minerals through Lhoist North America.
• USLM drivers: Pricing power and high margins; Fortress balance sheet and capital returns.

A faster-growing, richer-valued name usually swings harder, so it suits a longer horizon and a higher tolerance for volatility; a steadier, more cash-generative business suits a more conservative or income-minded investor. The honest test is which set of risks you could hold through a drawdown: Construction cycle volatility. For USLM, demand is cyclical and tied to construction, industrial production, and energy activity, so a downturn in any of those pressures volumes, as seen in the first quarter of 2026 when revenue fell about 3.7%.

Growth-minded investors who believe the theme has years to run tend to accept the richer multiple for more upside; value-minded investors lean toward the cheaper forward earnings and steadier profile. Pick MLM if you believe its drivers more; USLM if you believe its. Many investors hold both, but since they share themes, that is a concentrated bet, not diversification. Decide deliberately and check overlap. For the full detail, see the MLM and USLM guides.

MLM. Martin Marietta trades at about 32.5x trailing and 23x forward earnings, a premium that has compressed as the shares fell about 21% this year while 2026 earnings are expected to dip about 9% before rebounding about 25% in 2027 with Lhoist included. The 24 covering analysts hold a buy consensus with a mean target near $634, though most have trimmed targets since late September.

USLM. At ~$107 the stock trades near 23 times trailing earnings of ~$4.67, about 19 times the ~$5.70 analysts expect for 2027, and about 8 times sales, still rich for a materials company and a reflection of its ~41% operating margin and ~$403 million cash pile against almost no debt. The multiple has compressed as the share price fell ~19% over the past year while earnings kept rising. The token dividend understates capital returns, since the company has historically paid special dividends on top of the regular payout.

Headline figures (approximate, October 2026): MLM shows revenue (ttm) ~$6.7 billion; Q2 2026 revenue up 21% year over year to a record ~$1.95 billion, operating margin ~20%, eps (ttm) ~$15.42; forward ~$21.90, p/e ~32.5x trailing, ~23x forward; USLM shows revenue (ttm) ~$377 million, revenue (q2 2026) ~$99.1 million, up ~8.3% year over year, net income (ttm) ~$134 million (~36% net margin), diluted eps (q2 2026) ~$1.20 vs ~$1.30 estimate.

MLM and USLM are related but distinct: same themes, different businesses and risks. Neither wins in the abstract; the right pick is whichever thesis you actually believe, sized so you are not over-concentrated in one theme. Walnut can show your combined MLM and USLM exposure against your real portfolio. It is not an investment adviser.