Anthropic now has more business customers than OpenAI, according to Ramp data

Anthropic has, for the first time, surpassed OpenAI in the number of verified business customers, according to the latest AI Index from fintech firm Ramp. The survey, based on expense data from Ramp's clients, indicates that 34.4% of participating businesses are now paying for Anthropic's services, compared to 32.3% for OpenAI. This marks a significant milestone for Anthropic, which previously lagged behind its competitor.

Anthropic has shown particular strength among "high adoption groups" such as finance, technology, and professional services. While OpenAI still holds a lead in other sectors, that gap has been steadily closing in recent months. This trend is not isolated, as other industry indicators, like OpenRouter's leaderboard, also show Anthropic gaining ground on OpenAI.

The past year has been transformative for Anthropic, with its business adoption climbing by 26% from May 2025 to May 2026, when it started at a mere 9%. In contrast, OpenAI's share declined by 1% over the same period. This growth highlights Anthropic's successful strategy of initially focusing on a technical customer base, executing effectively, and then broadening its reach with tools like Cowork.

Although the Ramp index represents only a segment of the market, comprising over 50,000 companies, its breadth and diversity lend it considerable weight. The overarching trend observed across various platforms suggests a notable shift in the competitive landscape of the AI industry.