Are Quantum Computing Stocks in a Bubble?

Quantum computing stocks have taken Wall Street by storm. Since the start of the third quarter of 2024, investors have piled into the three pure-play quantum stocks -- IonQ (NYSE: IONQ), D-Wave Quantum (NYSE: QBTS), and Rigetti Computing (NASDAQ: RGTI) -- resulting in eye-popping gains for early shareholders. Rigetti has rocketed 4,330%, D-Wave surged 3,330%, and IonQ climbed 812%.

Still, these companies are developing a technology that's basically in its infancy -- think of the telegraph when Alexander Graham Bell was tinkering with the telephone. Moreover, all three stocks sport valuations that would make even the most aggressive venture capitalists blush.

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Are quantum computing stocks in a bubble? Let's examine the field's current state and long-term potential to determine its future direction.

The valuation reality check

IonQ leads the pack with a $22.4 billion market cap but trades at 303 times trailing sales. The company's trapped-ion technology operates on cloud platforms such as Amazon's AWS, Microsoft Azure, and Alphabet's Google Cloud. In October 2025, the company secured $2 billion in equity financing from Heights Capital Management, the largest single institutional investment in quantum computing history. With an estimated 2026 revenue of $162 million, IonQ generates the most revenue among pure plays, but that $22 billion valuation still prices in decades of explosive growth.

D-Wave Quantum takes a different approach, with quantum annealing technology optimized for optimization problems. Trading at 335 times trailing sales with a $12.6 billion market cap, D-Wave already serves over 100 customers, including Volkswagen and Lockheed Martin, on real-world logistics and supply chain problems. The estimated 2026 revenue of just $38.2 million makes the valuation look particularly stretched, however.

Rigetti Computing sports the most extreme valuation, at 1,111 times trailing sales. The company's $11.5 billion market cap towers over the estimated 2026 revenue of only $21.5 million. Rigetti Computing controls the full stack, from chip fabrication to cloud delivery, positioning itself as a vertically integrated quantum provider.

Why this might not be 1999 all over again

These price-to-sales multiples scream bubble. But three factors distinguish quantum's current moment from classic bubble dynamics. Major technology platforms, including Nvidia, Amazon, Microsoft, and Alphabet, are building quantum teams and investing in hardware development. When hyperscalers deploy capital at scale, they're signaling conviction in near-term commercialization.

Government urgency around "Q-Day" -- when quantum computers break current encryption standards -- is also driving unprecedented funding and regulatory support. Defense agencies are treating quantum as strategic infrastructure, creating a guaranteed customer base and funding backstop that didn't exist for 1990s internet companies.

Unlike dot-com companies burning cash on Super Bowl ads, quantum companies have actual technology solving real problems today. McKinsey estimates that quantum could unlock $200 billion to $500 billion in pharmaceutical value by 2035 through drug discovery acceleration.

Battery simulations that classical computers can't handle could enable 50% higher energy density -- transforming electric vehicle economics. The revenue is tiny, but it's growing. An ocean of revenue awaits the first company to build a truly functional quantum computer.

Are quantum computing stocks in a bubble?

Partly yes. Current valuations assume a one-hundred-billion-dollar market within a decade and early movers taking outsize share. If progress stalls or classical advances close the gap, these stocks could fall hard.

There is also a rational core. At similar stages, cloud leaders and artificial intelligence (AI) infrastructure names carried rich multiples. Nvidia sustained a high valuation through long winters before results arrived. Quantum targets problems that overwhelm classical methods in chemistry, materials, and optimization, creating ocean-sized markets from scratch.

Call it speculative with real upside. It will look like a bubble if error rates do not fall, scale does not arrive, and customers do not pay. It will look justified if fault tolerance improves, useful problem sizes appear, and revenue compounds. The verdict depends on execution, not narrative.

George Budwell has positions in D-Wave Quantum, IonQ, Lockheed Martin, Microsoft, Nvidia, and Rigetti Computing. The Motley Fool has positions in and recommends Alphabet, Amazon, Microsoft, and Nvidia. The Motley Fool recommends Lockheed Martin and Volkswagen Ag and recommends the following options: long January 2026 $395 calls on Microsoft and short January 2026 $405 calls on Microsoft. The Motley Fool has a disclosure policy.