Quick answer
OpenAI's scheduled retirement of o3 from ChatGPT took effect on August 26, 2026. OpenAI says this is a ChatGPT-only change and does not change API access. Chat AI's current model catalog includes o3, although model access can change by plan, platform, region, and app version.
What changed on August 26
OpenAI removed o3 from ChatGPT after a 90-day sunset period announced on May 28. The retirement affects the ChatGPT model picker, where o3 had been available to paid users through model settings. OpenAI did not describe this as a new model launch or an o3 capability update.
Sources: OpenAI Help Center
The retirement applies to ChatGPT, not the API
OpenAI explicitly says the o3 retirement applies only to ChatGPT and that there are no API changes. Its API model directory continues to list o3 as a reasoning model for complex tasks. That distinction matters because a model can disappear from one first-party product while remaining available to developers and other products through the API.
Sources: OpenAI Help Center, OpenAI
What ChatGPT users should do
If you used o3 in ChatGPT, check the current model picker and choose a supported model based on the task rather than assuming an exact replacement. Re-run a few representative prompts before moving an important workflow, especially for reasoning, coding, file analysis, or image-heavy work. OpenAI's current release notes identify GPT-5.6 Sol as its flagship reasoning model for eligible paid ChatGPT plans, but access can vary by product and plan.
Sources: OpenAI Help Center
o3 is currently listed in Chat AI
Chat AI's public model directory lists o3 as a Pro model. Because OpenAI says the retirement does not change its API, that listing is not contradicted by o3 leaving ChatGPT. Availability can still change by plan, platform, region, provider access, and app version, so check the live model selector before relying on it for a time-sensitive workflow.
Sources: OpenAI Help Center, Chat AI
Frequently asked questions
What readers usually ask
Was OpenAI o3 retired everywhere?
No. OpenAI says the August 26 retirement applies to ChatGPT only and that there are no changes to the API.
Can developers still use o3 through the OpenAI API?
OpenAI's retirement notice says there are no API changes, and its API model directory continues to list o3. Developers should still check their account's current model access before depending on it.
Is o3 available in Chat AI?
Chat AI's public model directory lists o3 as a Pro model at publication time. Availability can change, so confirm it in the current app model selector.
Which model replaces o3 in ChatGPT?
OpenAI's retirement notice does not name a one-to-one replacement. Its current release notes describe GPT-5.6 Sol as the flagship reasoning model for eligible paid plans, but the right choice depends on the task and current plan access.
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