OpenAI is closing the gap on Anthropic among US business customers
New spending data from 70,000 American companies shows Anthropic still leads, but OpenAI is growing faster right now. The real story is how quickly businesses are willing to switch.
Key points
- Anthropic held nearly 44% market share among Ramp's business customers in July 2026, versus OpenAI's nearly 40%.
- OpenAI lost its lead among business users in May 2025, when Anthropic first hit 41% market share.
- More than 56% of companies on Ramp's platform paid for AI tools by July 2026, up from just over 50% in March 2025.
- OpenAI is currently growing faster than Anthropic in the third quarter of 2025 so far, according to Ramp economist Ara Kharazian.
For a long time, OpenAI looked unbeatable. Then businesses started switching.
Ramp, a corporate credit card and expense-management company used by more than 70,000 American businesses, tracks which AI services those companies actually pay for. Its latest data, first reported by TechCrunch AI, shows Anthropic still ahead but OpenAI pulling closer. Ramp's own Router service, which we covered on 20 August, lets those same businesses swap between OpenAI, Anthropic and others through a single interface, so the switching costs we describe below are even lower for Ramp customers than for most.
Who is winning right now?
Anthropic leads, but the gap is narrowing. As of July 2026, Anthropic holds nearly 44% of AI spending among Ramp's customers, against OpenAI's nearly 40%. OpenAI had been the clear front-runner until May 2025, when Anthropic overtook it and hasn't given the lead back since.
OpenAI is growing faster than Anthropic in the third quarter of 2025 so far. Kharazian points to GPT-5.6 Sol, OpenAI's latest model, as a reason developers are choosing OpenAI again. He also notes that Anthropic's higher-end model tier, called Fable, disappointed some customers on price and because regulators require Anthropic to retain Fable users' data for 30 days.
| Date | Anthropic share | OpenAI share | Companies paying for AI |
|---|---|---|---|
| May 2025 | 41% | 39% | topped 50% |
| July 2026 | ~44% | ~40% | ~56% |
A few caveats matter. Ramp's customer base skews toward technology companies. Large enterprises often use expense tools from providers like American Express and aren't counted here. Ramp shared only percentages, not actual dollars spent.
What does this mean for ordinary businesses?
Switching is easy, and companies are doing it freely. A business that paid for Claude last quarter might pay for ChatGPT next quarter, then switch back. That restlessness tells you no single AI provider has made itself truly essential, the way a payroll system becomes embedded in daily operations and painful to leave.
Kharazian called this a quarter still in progress, and he's right to hedge. A month remains in Q3 2025, and a major new model release from either lab could flip the numbers again.
Good news is buried in all this. Both companies can grow revenue even while fighting each other for share, because the overall market keeps expanding. The share of Ramp's customers paying for any AI tools at all topped 50% in March 2025 and reached nearly 56% by July 2026.
What should businesses watch for?
If your company's locking into a long AI contract, read the data-retention terms before you sign. Anthropic's 30-day retention requirement on Fable caught some customers off guard. Check what your chosen provider does with your data, how long they keep it, and whether that fits your industry's rules.
Pricing models change quickly too. What looks cheap today may not be cheap when the next model tier lands. Keep your contracts flexible where you can.
