Simile raises $200M Series B at $2B valuation for AI human behavior simulations

Simile, a Stanford-founded AI startup building foundation models of human behavior, closed a $200 million Series B at a $2 billion post-money valuation on July 30, 2026, led by Greenoaks. The round arrives just five months after a $100 million Series A that launched the company publicly in February 2026, bringing disclosed funding to more than $300 million in under six months—one of the steepest funding trajectories for enterprise AI in 2026. Index Ventures doubled down, while Hanabi, Bain Capital Ventures, A*, Factory, CVS Health Ventures, and Definition joined as participants.

Simile's pitch: simulate entire populations of synthetic users ("agentic twins") to predict how real customers, patients, and employees will behave before companies commit budget. The company trained foundation models on 1,000 representative interviews plus several million respondents via Gallup, claiming 85– 99% accuracy by segment. CVS Health used 400,000 synthetic patients to test medication adherence strategies; Deloitte, Wealthfront, and Gallup are other customers. Since public launch, Simile reports fivefold revenue growth and headcount expanded to 50+ employees. The new capital funds foundation model training, compute scaling, and commercial expansion across healthcare, financial services, and media.

For practitioners: Simile's hypergrowth funding signals enterprise appetite for behavioral AI as a decision-testing layer before market deployment. However, the startup's trajectory also highlights investor herd risk—six-month unicorn status on a team that emerged from stealth raises questions about market verification versus narrative momentum. The core value depends on whether synthetic agents truly capture real-world behavior variation or merely reflect the biases of their training data. Early customers are real, but the premise (that simulated humans can replace market research) is contested by rivals like Helm and Artificial Societies.