Ramp Data Confirms Anthropic Now the Most Adopted AI in US Business

30-Second Summary

For the first time, Anthropic's Claude has overtaken OpenAI's ChatGPT in US business adoption, according to the June 2026 Ramp AI Index. Ramp tracks real corporate card and billing data across more than 50,000 US companies, making this one of the most reliable signals of where enterprise AI spend is actually going. Anthropic sits at 41% of businesses with paid AI subscriptions. OpenAI is at 39.5% and effectively flat. Three years ago, Anthropic did not register in the data at all.

At a Glance

• Topic: Enterprise AI
• Company: Anthropic (reported via Ramp)
• Date: June 13, 2026
• Announcement: June 2026 Ramp AI Index shows Anthropic leads OpenAI in US business AI adoption for the first time
• What Changed: Anthropic reached 41% of businesses with paid AI subscriptions, up 2.5 percentage points. OpenAI fell 0.1 percentage points to 39.5%.
• Why It Matters: This is real spend data, not consumer downloads or sign-ups. It measures which AI products businesses are actually paying for.
• Who Should Care: Any business operator currently running on OpenAI by default, and any team making AI vendor decisions in the next six to twelve months.

Key Facts

• Anthropic: 41% of US businesses with paid AI subscriptions (up 2.5pp from May 2026)
• OpenAI: 39.5% (down 0.1pp, essentially flat)
• Anthropic's lead over OpenAI: 1.5 percentage points
• Anthropic three years ago (June 2023): 0.03% of businesses
• Data source: Ramp corporate card and billing data, 50,000+ US businesses
• Report published: June 13, 2026

What Happened

Ramp, the corporate card and finance automation platform, publishes a monthly AI Index tracking which AI tools US businesses are paying for. The data comes from actual billing records, not self-reported surveys. In the May 2026 edition, Anthropic crossed OpenAI for the first time. The June 2026 edition, published on June 13, confirmed the shift is holding and accelerating.

Anthropic grew from 34.4% in April 2026 to 41% in June 2026, adding 2.5 percentage points in the most recent month alone. OpenAI, by contrast, dropped 0.1 percentage points to 39.5% and has been essentially flat since the crossover began. The gap has widened from 2.1 percentage points in May to 1.5 percentage points in June, depending on measurement, with Ramp noting methodological updates to better capture enterprise spend on both platforms.

The growth trajectory for Anthropic is difficult to overstate. In June 2023, Anthropic registered 0.03% penetration in Ramp's business dataset. By April 2025, that number had reached 7.94%. By April 2026 it was 34.44%, and by June 2026 it is 41%. That is a 1,300-fold increase over three years, with most of the growth concentrated in the last twelve months.

OpenAI still holds a significant position in the market and has not lost business at scale. But its growth has stalled. OpenAI grew US business adoption by only 0.3% over the past year, compared to Anthropic's near-quadrupling in the same period.

Why It Matters

Enterprise AI vendor decisions are consolidating faster than most operators realise. The window for businesses to run informal AI experiments is closing. Finance teams are now authorising ongoing subscriptions. The question is no longer which AI to try, it is which AI to build on.

The competitive dynamic has structurally shifted. For three years, "use ChatGPT" was the default response to any AI request in a business setting. That default is now empirically incorrect. The majority of US businesses paying for AI are paying for Claude.

Safety and governance are influencing procurement decisions. Anthropic's Constitutional AI approach and its positioning on enterprise governance have resonated with legal, compliance, and IT security teams who influence or control software purchasing. This is not a developer-led adoption curve. It is a broader organisational uptake.

OpenAI's strengths are still real but increasingly contested. ChatGPT Enterprise remains strong, and OpenAI has significant API penetration among developers. But in the mid-market businesses that make up the bulk of Ramp's dataset (10 to 500 employees), Anthropic is now the more common choice.

The risks to Anthropic's position are worth tracking. Analysts have flagged three threats: compute costs that scale with usage, supply constraints as Anthropic's model demand outpaces infrastructure, and a token-pricing model that becomes expensive for heavy users. None of these have materialised as adoption killers yet, but they are the most credible challenges to Anthropic's current trajectory.

The David and Goliath View

The Ramp AI Index matters because it is one of the few data sources that measures what businesses actually pay for, not what they say they prefer in a survey or what their IT team approved in theory. Spend data is the truth. And the truth in June 2026 is that the majority of US businesses paying for AI have chosen Anthropic.

For operators who built early workflows on OpenAI, this does not require an immediate switch. OpenAI remains capable and broadly available. But it does require a reassessment. If your AI strategy is "we use ChatGPT", you are now describing the minority position in US enterprise. The question is whether you are there by deliberate choice or by inertia. Those are very different answers to give to your board.

The deeper implication is about what drove the shift. Anthropic did not win on speed to market or consumer brand recognition. It won by being the choice of enterprise buyers who had governance, legal review, and compliance in their procurement process. That is a durable advantage. Enterprises that go through that process tend to stay with their decision.

Where This Fits in the AI Stack

The Ramp AI Index measures the application layer, specifically which AI products businesses pay for at the surface level. Below that layer sits the API and model infrastructure, where OpenAI still has significant developer penetration. The enterprise adoption gap will eventually filter down to API and tool choice, but the billing layer typically moves first.

For operators building internal tools, the Ramp data is a leading indicator of where your own organisation's AI defaults are heading. The businesses in Ramp's dataset are the same businesses hiring talent, choosing software, and setting procurement policies. When 41% of them pay for Claude, that shapes what AI literacy your future hires arrive with.

Questions Operators Are Asking

Does this mean I should switch from OpenAI to Anthropic? Not automatically. If your current workflows are working well on OpenAI, switching carries migration costs and risks. But it does mean you should benchmark your use case on both platforms, because the assumption that OpenAI is the default best choice is no longer supported by market data.

What is driving businesses to choose Anthropic over OpenAI? The most credible explanations are governance and safety positioning (Claude's Constitutional AI resonates with enterprise procurement), product quality on longer reasoning tasks, and the availability of Claude for Work and Claude Enterprise at competitive price points.

Is this data reliable? Ramp's dataset covers more than 50,000 US businesses using their corporate card. It measures actual billing transactions, not surveys or downloads. It is the closest thing available to ground truth on enterprise AI spend. Ramp notes it updated its methodology in June 2026 to better capture OpenAI and Anthropic enterprise spend, so the June figures are more accurate than prior months.

What happens if Anthropic's costs increase significantly? This is the main risk analysts are flagging. Anthropic's token-based pricing means that as usage scales, costs scale with it. If Anthropic raises prices or compute costs increase without corresponding efficiency gains, some businesses may revert to OpenAI or move to open-source alternatives.

What does this mean for businesses that have not yet committed to an AI platform? You are making the decision at the point where Anthropic is the market leader. That makes Claude a reasonable starting point for evaluation. But the decision should still be driven by your specific use case, your data security requirements, and the tools your team will actually use.

Citable Summary

The June 2026 Ramp AI Index, based on corporate card spend from more than 50,000 US businesses, shows Anthropic's Claude at 41% business adoption versus OpenAI's ChatGPT at 39.5%. It is the first time Anthropic leads OpenAI in this dataset. Anthropic grew from 0.03% of US businesses in June 2023 to 41% in June 2026, a trajectory driven in part by enterprise governance and compliance requirements. Analysts flag rising compute costs, supply constraints, and token-based pricing as the primary risks to Anthropic's position.