CLS vs PLXS: Which Is the Better Buy in 2026?

Same yardstick, side by side (as of August 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: CLS 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. CLS and PLXS 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 CLS and PLXS 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.

Celestica is a Toronto-based electronics manufacturing services (EMS) and supply-chain company that designs, builds, and tests hardware for other companies. It reports in two segments. Connectivity & Cloud Solutions (CCS) is the larger and faster-growing one, serving data-center and communications customers with networking switches, servers, storage, and increasingly custom AI/ML compute hardware; in Q1 2026 CCS was about ~80% of total revenue and grew roughly ~76% year over year, with hyperscaler customers making up the majority of that segment. Advanced Technology Solutions (ATS) is the diversified segment covering aerospace and defense, industrial, HealthTech, and capital equipment. The company makes money on the volume and complexity of the hardware it manufactures and on higher-value design and joint-design-manufacturing (JDM) work, where margins are structurally better than commodity contract assembly.

Full CLS guide

Plexus Corp (NASDAQ: PLXS), headquartered in Neenah, Wisconsin and operating since 1979, is a contract electronics manufacturer that provides integrated lifecycle solutions spanning design and development, supply chain, new product introduction, manufacturing, and aftermarket services. Unlike the scale-driven giants of the EMS industry, Plexus deliberately targets mid-to-low volume, higher-complexity programs in three regulated sectors: Aerospace/Defense, Healthcare/Life Sciences, and Industrial. Its work includes life-saving medical devices, mission-critical defense electronics, industrial automation, and semiconductor capital equipment, where certifications, traceability, and engineering rigor matter more than raw volume economics.

Full PLXS guide

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

• CLS drivers: Hyperscaler-driven CCS growth; AI networking and compute content.
• PLXS drivers: Regulated-market specialization; Program ramps and revenue momentum.

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: Customer concentration is the headline risk: as of Q1 2026 three customers each represented at least 10% of revenue (roughly 35%, 15%, and 15%), and the top ten customers made up about ~78% of revenue, so losing or being de-prioritized by a single hyperscaler would matter a lot. For PLXS, the most cited risk is valuation: the stock has roughly doubled in a year and trades at a premium price-to-earnings multiple, creating meaningful downside if growth or margins disappoint.

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 CLS if you believe its drivers more; PLXS 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 CLS and PLXS guides.

CLS. These figures are tied to the June 2026 reporting picture and Celestica's Q1 2026 results announced in late April 2026. The company has repeatedly beaten and raised guidance on AI-driven demand, and its valuation multiple has expanded well above its historical EMS range to reflect those growth expectations. A premium multiple means the stock is more sensitive to any disappointment in growth or margins than a traditional contract manufacturer would be.

PLXS. Plexus generates roughly $4.1 billion in trailing revenue and around $173 million in net income, with fiscal Q2 2026 setting a quarterly revenue record near $1.16 billion. The stock has roughly doubled over the prior year, lifting its trailing P/E into the mid-to-high 30s and its forward P/E to the high 20s to low 30s. That places it at a premium to its own history and richer than several EMS peers, reflecting optimism about margin expansion that has already been partly priced in.

Headline figures (approximate, June 2026): CLS shows q1 2026 revenue ~$4.05B (up ~53% YoY), ccs segment growth ~76% YoY in Q1 2026 (~80% of revenue), 2026 revenue guidance ~$19B (raised from ~$17B), adjusted operating margin ~8.0% Q1 2026; ~8.1% 2026 guide; PLXS shows revenue (ttm) ~$4.1B, net income (ttm) ~$173M, fiscal q2 2026 revenue ~$1.16B (record), fiscal q2 2026 non-gaap eps ~$2.05.

CLS and PLXS 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 CLS and PLXS exposure against your real portfolio. It is not an investment adviser.