ASX vs IMOS: Which Is the Better Buy in 2026?
Last updated August 2026
Short answer
ASX is the larger of the two ($77.33B market cap): the incumbent the market prices for continued execution (19.11x forward earnings, beta 1.46). IMOS is the smaller challenger ($1.65B), actually pricier on forward earnings (46.93x): 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.
ASX vs IMOS: the tie-breaker metrics
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.
| Metric | ASX | IMOS | What it tells you |
|---|---|---|---|
| Market cap | $77.33B | $1.65B | Size. The larger name is the incumbent; the smaller has more room to grow and more to prove. |
| Forward P/E | 19.11 | 46.93 | 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. |
| Trailing P/E | 43.42 | 61.56 | Valuation on the last 12 months. A big drop from trailing to forward means the market expects earnings to jump, so more growth is already in the price. |
| Beta | 1.46 | 1.30 | 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 | 71% of range | 51% 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 | 6.43 | 2.18 | How much you pay over book value. Very high can signal an asset-light, high-return business or a rich price. |
Reading it: ASX 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.
Before you buy: how ASX and IMOS 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. ASX and IMOS 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 ASX and IMOS 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 ASE Technology Holding (ASX) do?
ASE Technology Holding (NYSE: ASX; TWSE: 3711) is the parent of Advanced Semiconductor Engineering and SPIL, together the largest provider of outsourced semiconductor assembly, test, and materials (the ATM segment) in the world. It also runs a sizable electronics manufacturing services (EMS) business through USI. The ATM segment packages and tests chips designed by fabless firms and manufactured by foundries, and it has become strategically central to AI computing through advanced packaging technologies such as fan-out wafer-level packaging, system-in-package, and support work tied to 2.5D/3D integration used in AI accelerators and high-bandwidth memory.
What does ChipMOS Technologies (IMOS) do?
ChipMOS Technologies provides back-end semiconductor services: it assembles and tests chips for fabless designers, integrated device manufacturers, and foundries. Its specialties include memory packaging and testing plus a leading position in chip-on-film (COF) packaging for display driver integrated circuits (DDICs) used in smartphone and TV panels, alongside services like wafer bumping, ball grid array (BGA), and wafer-level chip-scale packaging. The company runs facilities in Taiwan's Hsinchu and Southern Taiwan science parks and is listed both in Taipei (8150) and on Nasdaq as an ADR (IMOS).
ASX vs IMOS: 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.
- ASX drivers: AI-driven advanced packaging; Scale and market leadership.
- IMOS drivers: AI-driven memory demand; Chip-on-film and display-driver niche.
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: ASX is deeply cyclical and its results swing with semiconductor demand, inventory corrections, and smartphone and PC seasonality. For IMOS, chipMOS is a small OSAT competing against giants like ASE and Amkor and specialist peers like Powertech, so it lacks their scale, diversification, and pricing power.
ASX or IMOS: 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 ASX if you believe its drivers more; IMOS 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 ASX and IMOS guides.
ASX vs IMOS: the full fundamentals
ASX. ASE reported Q1 2026 net revenue of about NT$173.7 billion, up roughly 17 percent year over year, with net income near NT$14.1 billion and EPS around NT$3.24, both up sharply from a year earlier. Q2 2026 revenue reached about NT$191 billion (roughly US$6.05 billion), up about 27 percent year over year. At a market cap near $93 billion and a forward P/E in the mid-to-high 20s, the stock prices in continued AI-packaging growth against a cyclical, capital-heavy base.
IMOS. The trailing P/E looks extreme (near 98) because 2025 net profit fell about 65 percent year over year, compressing the earnings base, while the forward P/E of roughly 26 reflects expected recovery. The ADR rose more than 280 percent over the trailing 52 weeks on the AI memory upcycle, so the valuation now embeds a continued rebound in packaging and test demand.
Headline figures (approximate, JULY 2026): ASX shows market cap ~$93 billion, revenue (ttm) ~$21 billion, q1 2026 revenue ~NT$173.7 billion (up ~17% YoY), q1 2026 gross margin ~20%; IMOS shows revenue (ttm) ~$792M, net income (ttm) ~$26M, gross margin ~12%, market cap ~$2.5B.
The bottom line: ASX vs IMOS
ASX and IMOS 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 ASX and IMOS exposure against your real portfolio. It is not an investment adviser.
Wondering how ASX or IMOS fits the portfolio you already own? Walnut is an AI investing app that connects your brokerage read-only and answers questions like that about your actual holdings: overlap, concentration, and how each position tracks the S&P 500. Compare the best AI portfolio analyzers or see the best AI investing apps in 2026.
Investing in ASE Technology Holding with AI
Connect the broker you already use and ask Walnut's AI how ASX fits what you actually hold: whether you own it already through a fund, what it would do to your concentration, and how it has tracked the S&P 500. Read-only by default, and you approve anything before it reaches your broker.
FAQ
What is the difference between ASX and IMOS?
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ASE Technology Holding (NYSE: ASX; TWSE: 3711) is the parent of Advanced Semiconductor Engineering and SPIL, together the largest provider of outsourced semiconductor assembly, test, and materials (the ATM segment) in the world. ChipMOS Technologies provides back-end semiconductor services: it assembles and tests chips for fabless designers, integrated device manufacturers, and foundries. 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 ASX or IMOS the better stock?
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Neither is universally better. ASX is the larger incumbent; IMOS is the smaller challenger and looks pricier 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, ASX or IMOS?
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On forward P/E (as of August 2026), ASX trades at 19.11x and IMOS at 46.93x, so ASX 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 ASX and IMOS?
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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 ASX vs IMOS?
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ASX: ASX is deeply cyclical and its results swing with semiconductor demand, inventory corrections, and smartphone and PC seasonality. Advanced packaging is capital-intensive, so heavy capacity spending can pressure returns if AI demand cools or capacity outruns orders. Customer concentration among a few large chipmakers, pricing competition from Chinese OSAT firms such as JCET and Tongfu that benefit from domestic localization policy, and thin EMS margins all weigh on the outlook. As a Taiwan-based operating company, ASX also carries New Taiwan dollar currency risk and elevated geopolitical exposure tied to cross-strait tensions, and the ADR can trade with added volatility versus the local shares. IMOS: ChipMOS is a small OSAT competing against giants like ASE and Amkor and specialist peers like Powertech, so it lacks their scale, diversification, and pricing power. Its revenue is concentrated in two volatile end-markets, memory and consumer display drivers, meaning a downturn in smartphone sales or memory prices hits results directly and severely. Net profit already fell sharply in 2025 on higher non-operating expenses and lower operating profit, and gross margins are thin (around the low teens), so earnings are highly cyclical. As a Taiwan-based ADR, the stock also carries currency, geopolitical, and cross-listing risks, and after a very large one-year run the shares trade at a rich trailing valuation that assumes the memory and AI upcycle persists.
Walnut is informational, not investment advice. This page is descriptive and not a recommendation to buy or sell ASX or IMOS; figures are approximate and dated (as of August 2026). Verify current data before investing.