3 min read
Quantum computing stocks are having the year of their lives. The benchmark quantum index is up more than 69% in 2026 while the S&P 500 has managed a comparatively pathetic 10.7%. There is just one small asterisk on this triumph: quantum computers still cannot do very much that is commercially useful. If that combination of soaring share prices and not-quite-ready technology rings a bell, congratulations, you were paying attention in 1999.
The mania
The numbers are real and they are spicy. The S&P Kensho Global Quantum Computing index has returned north of 69% this year, leaving the broader market eating its dust. Federal money is pouring in, with the US committing around $2 billion in incentives to the sector. Analysts have slapped “strong buy” ratings on the pure-plays. Retail investors have piled in with the enthusiasm usually reserved for meme stocks. Quantum is, right now, one of the hottest trades going.
The milestones are genuinely real, to be fair
And this is not pure vapour, which is what makes it interesting. There have been real engineering milestones this year. IonQ has deployed a 256-qubit system in Dublin, pushing into the European market. Rigetti’s 108-qubit machine reached general availability with a median two-qubit gate fidelity of 99.8%, a genuinely impressive number and the kind of reliability the field has chased for years. Quantinuum keeps advancing its hardware. The technology is moving forward, and faster than the sceptics predicted. So the excitement is not baseless.
The catch
Here is the sober bit. “Impressive for a lab” and “useful for your business” are still separated by a canyon. By analysts’ own estimates, the entire quantum computing market will be worth about $3 billion by 2028. That is not a typo, billion with a B, for a whole global industry, which is roughly what a single big tech firm now spends on AI data centres in a fortnight. The share prices are driven not by current revenue, which is tiny, but by the dream of “quantum advantage”, the still-hypothetical moment a quantum machine solves a valuable real-world problem faster than a classical one. That day may come. It has also been about five years away for roughly ten years running.
The market-watcher’s note (not investment advice)
None of this means quantum is a con. It means the stocks have sprinted far ahead of the science, which is a very specific and very familiar kind of risk. Bubbles can be built on real technology: the dot-com crash did not happen because the internet was fake, it happened because prices assumed the future had already arrived. If you own quantum stocks, be clear about what you actually own, which is a call option on a breakthrough that has not happened yet, priced as though it has. That can pay off enormously. It can also correct brutally the first time the hype cycle exhales. Position accordingly, and keep your own counsel on your own money.
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Did you know: “quantum advantage” is the threshold at which a quantum computer does something no classical computer realistically can. It has been demonstrated for deliberately contrived problems designed to favour quantum hardware, but not yet for a genuinely useful commercial one. That gap, between a clever lab stunt and a problem a business will pay to solve, is the entire investment case, and nobody knows exactly when it closes.