Anthropic will not go ahead with a scheduled price increase for Claude Sonnet 5, the company said this week, leaving the model’s introductory API rates in place indefinitely.
Anthropic launched Sonnet 5 in June 2026 at $2 per million input tokens and $10 per million output tokens, pricing it described at the time as a limited-time introductory rate running through August 31. A jump to $3 per million input tokens and $15 per million output tokens — a 50 percent increase on both ends — was due to take effect September 1.
In an update to its developer pricing documentation, Anthropic said the $2/$10 rate “is now the standard price” and that the September 1 increase “will not occur.” The company confirmed the change in a post from its official Claude account on X.
The reversal is specific to Sonnet 5’s API pricing — the per-token rate developers and businesses pay to build on Anthropic’s platform. Anthropic did not announce any change to its consumer subscription plans.
Timing
The decision comes as Anthropic works through preparations for what could become one of the largest public offerings in US history. The company, whose valuation has been pegged as high as $1.2 trillion in secondary-market trading, has reportedly begun meeting with prospective investors ahead of a possible Nasdaq listing this fall. Holding pricing steady removes one source of uncertainty for enterprise customers weighing multi-year contracts during that process.
It also lands amid intensifying competition on API pricing among frontier AI labs. Earlier this month, OpenAI cut the price of its GPT-5.6 Luna model by 80 percent and added a faster tier. For businesses that adopted Sonnet 5 expecting rates to rise, the freeze locks in the lower cost on every token processed going forward.