Atmus Filtration Technologies I (ATMU) Stock Price & How to Invest

Atmus Filtration Technologies designs and manufactures filtration products, principally under the Fleetguard and Nelson brands, for commercial trucks, construction and agricultural equipment, power generation and marine engines. The core products are unglamorous and consumable: fuel filters, lube filters, air filters, crankcase ventilation systems, coolant chemicals and exhaust components that wear out on a schedule and get replaced by a fleet mechanic, a dealer or an independent shop. Cummins carried the business for decades before spinning it out through a May 2023 IPO at $19.50 a share, then disposing of its remaining stake in March 2024. What is left is a roughly $1.8 billion revenue company with about 4,500 employees, a global distribution network reaching hundreds of thousands of service points, and specification positions on engine platforms that were locked in years ago.

The investment picture rests on the mix. Only about a fifth of sales are first-fit, the filters installed on a new engine at the factory. The rest is aftermarket, and because a filter installed today generates replacement demand for the life of the vehicle, the installed base is the real asset. That makes revenue far steadier than the Class 8 build cycle would suggest, and it is why gross margin has been grinding upward (28.6% in the first quarter of 2026, versus 26.5% a year earlier) even in a soft new-truck year. The newer story is diversification. The $456 million Koch Filter acquisition, closed in January 2026, created an Industrial Solutions segment selling air filters into commercial buildings and data centers, a market with no relationship to diesel engines at all. That segment ran a 21.9% adjusted EBITDA margin in its first partial quarter, above the legacy business. The counterweight is that the balance sheet now carries close to $1 billion of gross debt against roughly $400 million of book equity, and the long-run question of what happens to engine filtration in a lower-combustion world has not gone away.

The most obvious exposure is cyclical: first-fit volumes track new truck and off-highway equipment builds, and those have been pressured by tariffs, freight softness and uncertainty around 2027 model-year emissions rules. Tariffs cut two ways for Atmus, raising input costs on cross-border content while also lifting the price of the vehicles its filters go into. The balance sheet is now materially more levered after Koch, with about $998 million of total debt against roughly $210 million of cash and only about $404 million of book equity, which narrows the margin for error if end markets deteriorate. Competition is intense and consolidating fast, with Parker Hannifin agreeing to buy Filtration Group for roughly $9.25 billion and Donaldson adding Facet, meaning Atmus is one of the smaller players in a market of much larger diversified industrials. The long-horizon risk is powertrain mix: a genuine shift away from diesel would shrink the installed base that generates replacement demand, though the timeline for heavy-duty trucking is measured in decades rather than years. Finally, integration risk on Koch is real, since building industrial air filtration into a durable second leg requires capabilities the legacy business did not have.

5 analysts publish price targets on ATMU, averaging $66.00 against a $54.15 price as of August 2026, or +21.9%. The published targets run from $56.00 to $73.00, a narrow spread, and the ratings split 4 buy, 1 hold, 0 sell. Over the last six months there have been 2 raises and 5 cuts among the published actions. A price target is what an analyst published on a date, not a prediction, and sell-side ratings skew positive across the whole market.

Read the full ATMU forecast and price target for the target table, the recent rating actions by firm, and how the consensus has shifted.

We give no verdict on Atmus Filtration Technologies I. Both cases are real, which is why the question is contested at all, so here is the strongest version of each.

The case for buying. Aftermarket filtration demand. Roughly 80% of Atmus revenue comes from replacement filters, not filters shipped on new engines. The most optimistic published target, $73.00, assumes this works close to its best case.

The case against. The most obvious exposure is cyclical: first-fit volumes track new truck and off-highway equipment builds, and those have been pressured by tariffs, freight softness and uncertainty around 2027 model-year emissions rules. The most pessimistic target, $56.00, is roughly what ATMU is worth if this bites instead.

Read the full bull and bear case on ATMU, including what would have to change to break either one. Walnut is not an investment adviser.

A simple financial snapshot. These are approximations and refresh quarterly; for current figures see Atmus Filtration Technologies I's investor relations page or your broker.

• Revenue (TTM): ~$1.83B
• Net income (TTM): ~$211M
• EPS (TTM): ~$2.55
• Market cap: ~$4.4B
• P/E ratio: ~21x
• Dividend yield: ~0.4%

First quarter 2026 sales rose 14.6% to $477.5 million with adjusted EPS of $0.69, and full-year guidance calls for $1.945 billion to $2.015 billion of revenue, a 19.5% to 20.5% adjusted EBITDA margin and adjusted EPS of $2.75 to $3.00. At roughly 21 times trailing earnings the stock trades at a modest premium to the broader industrial group, which reflects the recurring aftermarket mix rather than the growth rate. Net debt sits near $789 million, or a little over two times adjusted EBITDA, following the Koch Filter purchase.

Other names that sit close to ATMU: same theme, named as a direct competitor, or held beside it in the same funds. Each entry says which. Worth a look if you are thinking about diversification within a thesis rather than concentration on one ticker.

There are three common ways to get ATMU exposure. Buy shares (or fractional shares) directly at any major broker. Hold an ETF that includes it, which spreads the position across many companies. Or build it into a focused thematic portfolio, so ATMU sits alongside other stocks that express the same thesis.

Walnut takes the portfolio route. Describe a thesis where ATMU fits (for example “AI infrastructure” or “dividend-growth large-caps”) and the AI proposes 5 to 6 constituents with target weights. You review the plan and fund it through your own broker when you're ready.

New to this? Start with how to invest in stocks, see how to analyze a stock with AI, or compare the best AI stock analyzers.

ATMU is a consumables business wearing a truck-parts label: the cycle sets the headlines, but the recurring filter replacement stream sets the earnings.

Whether ATMU is worth buying today depends more on your time horizon and what you already hold than on any single call. We walk through valuation, what would have to go right, and the risks in is ATMU a buy or a sell?, and where the stock could go from here in the ATMU stock forecast.

For income investors, whether ATMU pays a dividend and how the payout looks is covered in does ATMU pay a dividend? And to weigh ATMU against a peer, read the full side-by-side comparisons: ATMU vs PH and ATMU vs ETN.