The directory
Who's building quantum computers.
40 companies: 22 you can buy on a stock exchange and 18 private ones to watch. Each company is tagged with the qubit approach it is betting on, so you can see which technology your portfolio is exposed to.
| Company | Ticker | Approach | Based in | In short |
|---|---|---|---|---|
| IonQ | IONQ | Trapped ion | US | Largest pure-play by revenue; record Q1 2026 revenue of $64.7M. |
| Quantinuum | QNT | Trapped ion | US and UK | Listed on Nasdaq in 2026; Honeywell is a major shareholder. |
| Rigetti Computing | RGTI | Superconducting | US | Builds superconducting chips and sells cloud access. |
| IQM | IQMX | Superconducting | Finland | European superconducting maker. |
| D-Wave Quantum | QBTS | Annealing | US and Canada | Record $33.4M in Q1 2026 bookings. |
| Infleqtion | INFQ | Neutral atom | US | Listed on NYSE in 2026; strong in quantum sensing. |
| Xanadu | XNDU | Photonic | Canada | Light-based computers; listed on Nasdaq in 2026. |
| Quantum Computing Inc. | QUBT | Photonic | US | Photonic chips and optical systems. |
| Horizon Quantum | HQ | Software | Singapore | Tools for writing programs that run on many kinds of quantum hardware. |
| Arqit Quantum | ARQQ | Quantum-safe security | UK | Encryption designed to resist quantum attacks. |
| SEALSQ | LAES | Quantum-safe security | Switzerland | Chips with post-quantum cryptography. |
| BTQ Technologies | BTQ | Quantum-safe security | Canada | Post-quantum security infrastructure. |
| Quantum eMotion | QNC | Quantum-safe security | Canada | Quantum random number generation. |
| IBM | IBM | Superconducting | US | One of the longest-running quantum hardware programs. |
| Alphabet (Google Quantum AI) | GOOGL | Superconducting | US | Google's quantum hardware and error-correction research. |
| Microsoft | MSFT | Topological | US | Pursuing topological qubits and offers quantum cloud access. |
| Amazon (AWS) | AMZN | Cloud access | US | Runs the Braket cloud service and its own hardware research. |
| Intel | INTC | Silicon spin | US | Builds qubits with standard chip-making methods. |
| NVIDIA | NVDA | Software | US | GPU simulation and CUDA-Q software for hybrid quantum work. |
| Honeywell | HON | Investor | US | Major shareholder in Quantinuum. |
| Fujitsu | FJTSY | Superconducting | Japan | Superconducting machines and annealing-inspired solvers. |
| NEC | 6701 (Tokyo) | Annealing | Japan | Annealing systems for optimization problems. |
| PsiQuantum | Private | Photonic | US | Building large photonic machines with chip foundries. |
| Pasqal | Private | Neutral atom | France | A merger to go public was pending as of mid-2026. |
| QuEra Computing | Private | Neutral atom | US | Neutral-atom machines spun out of Harvard and MIT research. |
| Atom Computing | Private | Neutral atom | US | Neutral-atom systems built with large qubit counts. |
| planqc | Private | Neutral atom | Germany | Neutral-atom computers from Munich. |
| Alice & Bob | Private | Superconducting | France | Cat qubits designed to resist errors. |
| Oxford Quantum Circuits | Private | Superconducting | UK | Superconducting machines in data centers. |
| Nord Quantique | Private | Superconducting | Canada | Bosonic qubits with built-in error correction. |
| Alpine Quantum Technologies | Private | Trapped ion | Austria | Trapped-ion machines from Innsbruck. |
| Quantum Motion | Private | Silicon spin | UK | Silicon qubits made in standard chip fabs. |
| Diraq | Private | Silicon spin | Australia | Silicon spin qubits from Sydney. |
| Silicon Quantum Computing | Private | Silicon spin | Australia | Atom-scale silicon devices. |
| Photonic Inc. | Private | Photonic | Canada | Links silicon spin qubits with light. |
| Riverlane | Private | Error correction | UK | Error-correction software and hardware. |
| Q-CTRL | Private | Software | Australia | Software that reduces errors on today's machines. |
| Classiq | Private | Software | Israel | A platform for designing quantum programs. Intel agreed to buy it in Oct 2026; the deal is expected to close in 2027. |
| Quantum Machines | Private | Control systems | Israel | Electronics that control and read out qubits. |
| SandboxAQ | Private | Software | US | AI and quantum software, including quantum-safe security. |
Showing all 40 companies.
Listing status checked October 2026 against Quantum Zeitgeist and Motley Fool. Company revenue figures from TipRanks. Live prices for the pure plays are on the tracker.