IONQ or RGTI: Which Quantum Stock Has the Best Risk-Reward for 2026?

Core Insights - The quantum computing sector is rapidly evolving, with IonQ and Rigetti Computing attracting investor attention due to their distinct strategies and performances in 2025 [2][4]. IonQ Highlights - IonQ reported significant business expansion in 2025, with a sharp year-over-year increase in quarterly revenues and record technical benchmarks, including a world-record 99.99% two-qubit gate fidelity [7][10]. - The company achieved a cash position of $1.5 billion, which increased to $3.5 billion after a $2 billion equity raise, providing financial strength for future investments [8][10]. - IonQ's fifth-generation Tempo system is set to ship in 2026, demonstrating a computational space 36 quadrillion times larger than leading commercial superconducting systems [7]. Rigetti Highlights - Rigetti focused on superconducting quantum hardware, delivering modular quantum systems and expanding partnerships while investing heavily in infrastructure and R&D [3][12]. - The company aims to deliver a 100+ qubit chiplet-based system by the end of 2025, with a roadmap targeting a 150+ qubit system by late 2026 and a 1,000+ qubit system by late 2027 [12][13]. - Rigetti exited the third quarter with approximately $600 million in cash and no debt, allowing for continued investment in its roadmap [13]. Financial Performance - Year-to-date, IonQ shares have risen 8.3%, while Rigetti's stock has soared 45.9% [6]. - IonQ's adjusted EBITDA loss was $48.9 million in Q3 2025, while Rigetti reported revenues of $1.9 million and an operating loss of $20.5 million in the same period [11][14]. - Estimates for IonQ's 2026 loss per share have declined to $1.74, indicating a 65.8% improvement from 2025, while Rigetti's estimates have worsened to a loss of $0.18 per share, reflecting a 74.3% improvement from 2025 [15][16]. Valuation Comparison - IonQ is trading at a price-to-sales (P/S) ratio of 79.2X, higher than its five-year median of 76.1X, while Rigetti's P/S ratio is significantly higher at 220.28X [18]. Conclusion - IonQ is better positioned with faster commercial traction, record technical milestones, and a diversified quantum platform, supported by a strong cash balance of $3.5 billion [19]. Rigetti, while credible in its roadmap, has a smaller revenue base and is more dependent on future milestones [19].