Anthropic Overtakes OpenAI in Business Customers, Driven by Claude Model Growth

Anthropic has overtaken OpenAI in business customer volume for the first time.

April 2026 data from fintech firm Ramp shows 34.4% of US businesses with AI spending paid for Anthropic. OpenAI captured 32.3% of the same market during this period. This shift marks a significant reversal in a sector OpenAI previously dominated.

The Ramp AI Index analyzes corporate card and bill payment activity from tens of thousands of US businesses. Anthropic’s ascent reflects growing corporate momentum for its Claude family of models.

OpenAI disputes the methodology, stating the index fails to capture large enterprise contracts paid via invoice. Despite this, the Ramp data remains a primary barometer for business spending trends in the AI sector.