OpenAI is closing the gap with Anthropic in the competition for enterprise clients, driven by the offer of cheaper and more efficient AI models. In September, enterprise spending on tools from both companies was nearly tied, according to an analysis by OpenRouter, after Anthropic had captured about three-quarters of this market early in 2026.
The analysis includes approximately 120,000 companies that use products from OpenAI and Anthropic. The data indicates that the share of spending was close to 50% for each company in September. OpenRouter states that its base mainly includes AI-focused startups, as well as technology companies and large firms.
The shift gained momentum after OpenAI launched, in June, the GPT-5.6 family, composed of Sol, Terra, and Luna. The line offers models with different levels of capability and operational costs, allowing companies to use cheaper alternatives for tasks that do not require the most advanced systems. After the launch, OpenAI reduced the price of GPT-5.6 Luna by 80% and that of GPT-5.6 Terra by 20%.
The strategy has already influenced some companies. David Hsu, founder and CEO of the software development platform Retool, stated that the company has started to use primarily OpenAI models after the launch of GPT-5.6. According to him, the costs for the company's systems are currently about 20% lower than the costs for Anthropic models.
Despite the progress, leadership can still change. At the end of September, Anthropic began to make available the family Claude 5.5 , highlighting lower costs and higher efficiency. The competition occurs as both companies prepare for potential IPOs: Anthropic is working with the possibility of going public as early as November, while OpenAI may do so next year.
Ana Figueiredo is a technology editor at Olhar Digital. She is a graduate in Journalism from the Federal University of Uberlândia (UFU).
