CMI vs PLUG: How CMI and Plug Power Compare (2026)
Last updated July 2026
Short answer
CMI is the larger of the two ($93.27B market cap): the incumbent the market prices for continued execution (19.91x forward earnings, beta 1.22). PLUG is the smaller challenger ($3.68B), priced similarly on forward earnings (-16.07x): more room to run, but more to prove. The real question is which set of drivers you believe, and whether owning one (or both) leaves you over-concentrated.
CMI vs PLUG: the tie-breaker metrics
Same yardstick, side by side (as of July 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.
| Metric | CMI | PLUG | What it tells you |
|---|---|---|---|
| Market cap | $93.27B | $3.68B | Size. The larger name is the incumbent; the smaller has more room to grow and more to prove. |
| Forward P/E | 19.91 | -16.07 | Valuation on next year's expected earnings, the same yardstick for both. Lower is cheaper for that growth; higher means the market is paying up. |
| Beta | 1.22 | 2.12 | Volatility vs the market. Above 1 swings harder than the index; below 1 is steadier. Higher beta means bigger drawdowns to hold through. |
| Price vs 52-week range | 85% of range | 40% of range | Where today's price sits between the 52-week low and high. Near the high is momentum with less margin of safety; near the low is out of favor or a discount, depending on why. |
| Price / book | 7.55 | 4.91 | How much you pay over book value. Very high can signal an asset-light, high-return business or a rich price. |
Before you buy: how CMI and PLUG affect your concentration
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. CMI and PLUG 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 CMI and PLUG 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.
What does CMI (CMI) do?
Cummins Inc. is one of the world's largest independent makers of diesel and natural gas engines, and it operates across five segments: Engine, Components, Distribution, Power Systems, and Accelera (its low-carbon and electrification arm). Its products power heavy- and medium-duty trucks, buses, construction and mining equipment, and standby and prime power generators, and it runs a large aftermarket parts and service network. The Distribution segment is the largest by revenue, while Power Systems has been the fastest-growing thanks to demand for backup power at data centers.
What does Plug Power (PLUG) do?
Plug Power (PLUG) is a hydrogen and fuel-cell company building what it calls an end-to-end green hydrogen ecosystem. Its core legacy business is GenDrive fuel cells that replace lead-acid batteries in electric forklifts for large warehouse operators, with Amazon and Walmart as anchor customers. Beyond material handling, Plug sells electrolyzers (equipment that splits water into hydrogen using electricity), liquid hydrogen, cryogenic storage, and stationary power systems.
CMI vs PLUG: how do they differ?
Both fit overlapping themes, but they are not interchangeable. The useful comparison is which set of drivers and risks you want exposure to.
- CMI drivers: Data center backup power; North American truck cycle.
- PLUG drivers: Material handling base; Green hydrogen production.
Which fits which kind of investor
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: Cummins is exposed to the industrial and freight cycle, so a downturn in truck demand or construction spending can cut engine volumes and margins quickly. For PLUG, plug has a long history of operating losses, negative free cash flow, and repeated equity and convertible-debt raises that dilute shareholders.
CMI or PLUG: which should you pick?
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 CMI if you believe its drivers more; PLUG 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 CMI and PLUG guides.
CMI vs PLUG: the full fundamentals
CMI. Cummins trades at a premium to its historical multiple after a large 2025-2026 run tied to data center power demand. The forward P/E near 23x sits well below the trailing figure, reflecting expected earnings growth as guidance was raised. The dividend is modest in yield but backed by a long record of annual increases.
PLUG. Plug is a pre-profitability growth story valued on hydrogen-economy optionality rather than current earnings. Traditional valuation multiples are not meaningful given losses and dilution. The investment case rests on whether green hydrogen reaches cost parity and Plug reaches positive gross margin before exhausting capital, making it speculative and sentiment-driven.
Headline figures (approximate, JUNE 2026): CMI shows revenue (fy2025) ~$33.7B, revenue (q1 2026) ~$8.4B, up ~3% YoY, net income (fy2025) ~$2.8B, market cap ~$96B; PLUG shows revenue (ttm) ~$700 million, operating margin Deeply negative (large operating losses), net income (ttm) Net loss (~$1 billion range historically), free cash flow Negative (significant cash burn).
The bottom line: CMI vs PLUG
CMI and PLUG 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 CMI and PLUG exposure against your real portfolio. It is not an investment adviser.
Build a basket around CMI with Walnut
Use CMI as one constituent in a thematic basket Walnut's AI helps you assemble. Describe a thesis you believe in, the AI proposes the holdings and weights, and you approve before any broker order.
FAQ
What is the difference between CMI and PLUG?
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Cummins Inc. Plug Power (PLUG) is a hydrogen and fuel-cell company building what it calls an end-to-end green hydrogen ecosystem. They show up together because they share investment themes, but they are different businesses, so the better fit depends on which thesis you are expressing.
Is CMI or PLUG the better stock?
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Neither is universally better. CMI is the larger incumbent; PLUG is the smaller challenger and looks cheaper on forward earnings. Walnut is informational, not investment advice. Compare what each does, the tie-breaker metrics above, and the risks, then decide which fits your thesis and what you already own.
Which is cheaper, CMI or PLUG?
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On forward P/E (as of July 2026), CMI trades at 19.91x and PLUG at -16.07x, so PLUG is the cheaper of the two on next year's expected earnings. A lower multiple is not automatically the better buy: a richer valuation can be justified by faster growth, and a lower one can reflect real risk. Weigh the multiple against how fast each business is compounding.
Should you own both CMI and PLUG?
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Because they share themes, owning both concentrates you in that theme. That can be intentional (a focused bet) or accidental (less diversification than it looks). Walnut can show your combined exposure across both, and whether adding either over-concentrates you, before you buy.
What are the risks of CMI vs PLUG?
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CMI: Cummins is exposed to the industrial and freight cycle, so a downturn in truck demand or construction spending can cut engine volumes and margins quickly. The recent stock re-rating leaves valuation elevated versus history, which raises the bar for execution and makes the shares sensitive to any slowdown in data center power orders. Tightening or shifting emissions regulations can trigger costly product changes and demand pull-forwards or air pockets. Accelera continues to lose money and has produced restructuring charges, adding uncertainty. Tariffs, supply chain costs, and exposure to China and other international markets add further variability to results. PLUG: Plug has a long history of operating losses, negative free cash flow, and repeated equity and convertible-debt raises that dilute shareholders. Green hydrogen remains more expensive than fossil-derived hydrogen without subsidies, so demand outside incentivized material-handling and policy-driven projects is uncertain. Cash burn has periodically raised going-concern questions, and the company depends on capital markets staying open. Execution on production-plant ramps has slipped versus targets. The stock is highly volatile and sentiment-driven, swinging sharply on financing news, policy headlines, and quarterly cash levels rather than steady fundamentals.
Walnut is informational, not investment advice. This page is descriptive and not a recommendation to buy or sell CMI or PLUG; figures are approximate and dated (as of July 2026). Verify current data before investing.