ATS vs ROK: Which Is the Better Buy in 2026?

Same yardstick, side by side (as of November 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: ATS 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. ATS and ROK 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 ATS and ROK 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.

ATS Corporation, based in Cambridge, Ontario and founded in 1978, designs, builds, commissions and services automated manufacturing and assembly systems. The work is project-based: a pharmaceutical company that needs to fill and package a new auto-injector, or a utility running a nuclear refurbishment, hires ATS to engineer the line, integrate the robotics and vision systems, validate it against regulatory requirements, and then service it for years afterward. Fiscal 2026 (ended March 2026) revenue was about C$2.97 billion, up 17.4% reported and about 10.8% on an adjusted organic basis, with adjusted EBITDA of roughly C$413 million and free cash flow near C$372 million. Life sciences is the anchor market at roughly half of revenue, with energy (nuclear), food and beverage, and industrial and consumer making up the rest. The company listed on the NYSE in May 2023 and reports in Canadian dollars, so US investors carry a currency translation on top of the operating result.

Full ATS guide

Rockwell Automation (ROK) is one of the largest pure-play industrial automation and digital transformation companies in the world. It provides the hardware, software, and services that factories and industrial facilities use to run, monitor, and optimize their operations: programmable logic controllers, drives, motor control, sensors, industrial networking, and the Allen-Bradley and FactoryTalk product families that are standards in many North American plants. Rockwell organizes its business around Intelligent Devices, Software and Control, and Lifecycle Services, and increasingly pairs its installed base of automation hardware with software, analytics, and recurring services. A long partnership with software firms and its acquisitions in areas like manufacturing-execution software, cybersecurity, and information solutions position it to sell connected, data-driven factory systems, not just discrete controllers. Founded in 1903 and headquartered in Milwaukee, Wisconsin, Rockwell is an S&P 500 industrial that benefits from secular trends in reshoring, factory modernization, and the digitization of manufacturing, while remaining tied to the capital-spending cycles of its industrial customers.

Full ROK guide

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

• ATS drivers: Life sciences as the durable franchise; Nuclear and energy as the fastest-growing line.
• ROK drivers: Installed base and switching costs; Software, recurring revenue, and analytics.

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: ATS revenue is recognized on long-duration projects, so a handful of delayed customer awards can swing a quarter, and the June 2026 quarter is the live example: bookings down 5.3%, backlog down 8.7%, and a swing from C$24.3 million of net income to a small loss. For ROK, rockwell's results are tied to industrial and manufacturing capital-spending cycles, so demand can soften in downturns or when customers delay projects, and orders can be lumpy.

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 ATS if you believe its drivers more; ROK 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 ATS and ROK guides.

ATS. The selloff has pushed ATS to about 0.6 times sales and roughly 10 times EBITDA, while trailing GAAP earnings (net income of about 47 million over the last twelve months, after a loss in the March quarter and a near-breakeven June quarter) leave the trailing P/E above 50. The forward multiple near 13 assumes fiscal 2028 EPS recovers to about $1.36, which is a bet on the cost program and the nuclear plus radiopharmaceutical pipeline restoring margin before backlog erosion shows up in revenue. November 4, 2026 brings the next bookings print.

ROK. Rockwell trades at a premium multiple relative to the broader industrials group, a gap explained by its pure-play automation focus, strong installed-base moat, and growing software mix: ~40 times trailing GAAP earnings, ~29 times forward estimates and ~24 times EV/EBITDA as of October 16, 2026. The trailing multiple overstates the premium because GAAP earnings are still recovering from fiscal 2025; on analysts' fiscal 2027 estimate of ~$14.92 the stock is near 29 times. The 25 analysts tracked carry a mean target near $476, and the fiscal fourth-quarter report expected around November 5, 2026 is the next catalyst for the multiple.

Headline figures (approximate, October 2026): ATS shows revenue (fiscal 2026, ended march 2026) ~C$2.97 billion, up ~17.4% reported and ~10.8% adjusted, revenue (ttm through june 2026) ~2.93 billion; Q1 fiscal 2027 ~C$693.7 million, down ~5.8%, order bookings / backlog ~C$656 million booked in Q1 (down ~5.3%); backlog ~C$1,889 million (down ~8.7%), margins (ttm) Gross ~29%, operating ~7%, net ~1.6%; ROK shows revenue (ttm) ~$8.97 billion (June 2026 quarter up ~8% year over year), margins (ttm) ~49% gross, ~21% operating, ~13% net, net income (ttm) ~$1.2 billion; trailing EPS ~$10.68, adjusted eps, june 2026 quarter $3.49 vs ~$3.38 consensus.

ATS and ROK 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 ATS and ROK exposure against your real portfolio. It is not an investment adviser.