Anthropic Business Adoption Hits 30.6% in March, Closing Gap with OpenAI at 35%

AI market competition chart showing Anthropic rising vs OpenAI with bar graphs and neural network icons representing business adoption race

Anthropic's adoption among US businesses surged to 30.6% in March 2026 — up from 24.4% in February — while OpenAI's adoption remained nearly flat at around 35%, according to new data from business spend platform Ramp. The figures mark a dramatic narrowing of the gap between the two leading AI providers in just one month.

The Numbers

Ramp's March 2026 AI Index, which tracks actual business spending across its platform, shows Anthropic posting its largest month-over-month growth since tracking began. OpenAI, by contrast, experienced its largest-ever monthly decline — falling 1.5 percentage points — though it remains the market leader.

Among first-time AI buyers — businesses purchasing AI tools for the first time — Anthropic wins approximately 70% of head-to-head matchups against OpenAI. One year ago, only 1 in 25 businesses on Ramp paid for Anthropic. Today, nearly 1 in 3 does.

What's Driving Anthropic's Growth

Several factors are fueling Anthropic's rapid rise in enterprise adoption. Claude Code, Anthropic's AI coding tool, has become a breakout product among software development teams, with the company recently noting that interest in Claude Code products has been a primary driver of its recent rapid growth.

OpenAI's military contract controversy — which triggered internal protests and some enterprise pushback — has also helped Anthropic position itself as a more safety-focused and trust-aligned alternative for organizations concerned about how their AI provider handles sensitive partnerships.

OpenAI Still Leads, But the Trend Is Clear

OpenAI remains the dominant AI provider by total adoption, and its absolute customer base is still significantly larger than Anthropic's. However, the velocity of Anthropic's gains is what has observers paying close attention. At its current growth rate, Anthropic could potentially match or surpass OpenAI in business adoption within the next several months.

The competition is also intensifying as Google's Gemini models and Meta's Llama-based enterprise tools gain traction, fragmenting the market further.

The Bottom Line

The Ramp data paints a striking picture: Anthropic is not just growing — it's growing faster than any AI company has in enterprise spending data. Whether driven by Claude Code's productivity gains, brand trust, or OpenAI fatigue, the market is clearly rewarding Anthropic's approach. For enterprise buyers, the message is that the AI vendor landscape is no longer a one-horse race.