Quantinuum Prices $1.05B IPO — Largest Quantum Computing Public Offering Ever
Honeywell-backed Quantinuum is going public on Nasdaq as QNT at a $12.7B valuation, marking the first full-stack quantum computing company to reach public markets. Trading begins June 3–4.
Quantinuum is pricing its IPO at $45–$50 per share — 21 million shares, raising approximately $1.05 billion at a fully diluted market cap of around $12.7 billion. Nasdaq ticker: QNT. Trading starts June 3 or 4.
This is the largest quantum computing IPO in history, and the first full-stack quantum company to list publicly. Full-stack means Quantinuum builds everything: the trapped-ion hardware, the control software, the runtime, and the application layer on top. Most competitors sell access to bare quantum hardware through cloud APIs. Quantinuum’s pitch is different — vertical integration as a moat.
Honeywell retains ~49.1% of voting power post-IPO. Cambridge Quantum (the software division spun in and merged in 2021) holds ~32.5%. The company generated $30.9 million in full-year 2025 revenue and $5.2 million in Q1 2026. Those numbers are small relative to the valuation, but investors aren’t buying revenue — they’re buying a decades-long position on the assumption that fault-tolerant quantum systems become commercially critical infrastructure.
The trapped-ion approach Quantinuum uses is slower in raw gate speed than superconducting qubits (what IBM and Google use), but delivers far better error rates per gate. The company’s H2 processor achieved a 2-qubit gate fidelity above 99.9% — the benchmark that matters for eventually running circuits long enough to solve real-world problems. Error rates are the core argument for why this valuation isn’t purely speculative.
Reports indicate the company is considering boosting both share count and price range by roughly 10%, suggesting institutional demand is strong going into the pricing week.
There’s a legitimate debate about timing. Quantum advantage for commercially useful problems — factoring large integers, simulating novel drug molecules, solving NP-hard optimization — remains years away at minimum. But that’s exactly why some institutional investors want in now, before the technology is de-risked. The IPO structure (Honeywell retaining majority voting) means this won’t become a quick-flip target; the parent is clearly planning for a long arc.
For developers and researchers: Quantinuum’s Python SDK (InQuanto, TKET) is already shipping. The IPO doesn’t change your access to the hardware through the Microsoft Azure Quantum and Amazon Braket integrations, but public-company reporting will make the roadmap significantly more legible.
Watch the pricing finalization and first-day trading on or around June 4.