AI Catchup

GPT-5.4 Leaves ChatGPT-Signed-In Codex on August 31

By 2 min read

OpenAI says GPT-5.4 and GPT-5.4 mini will no longer be available to users signed in with ChatGPT starting August 31, 2026. The models remain available through the OpenAI API and Codex sessions authenticated with an API key.

OpenAI is changing where GPT-5.4 and GPT-5.4 mini can be used. OpenAI Developers says the models will no longer be available to users signed in with ChatGPT starting August 31, 2026. (OpenAI Developers on X)

The change is specific to the ChatGPT sign-in path. OpenAI says both models will remain available on the OpenAI API and in Codex sessions authenticated with an API key. (ChatGPT and Codex changelog)

What is changing

Access pathAfter August 31, 2026
Codex signed in with ChatGPTGPT-5.4 and GPT-5.4 mini are no longer available
OpenAI APIGPT-5.4 and GPT-5.4 mini remain available
Codex authenticated with an API keyGPT-5.4 and GPT-5.4 mini remain available

(OpenAI Developers on X, ChatGPT and Codex changelog)

This is an access-path change, not a statement that the models are being shut down everywhere. The announcement does not say that the API models are being renamed, repriced, or retired on that date.

Who needs to pay attention

The change matters most if your Codex workflow uses ChatGPT account authentication and explicitly selects GPT-5.4 or GPT-5.4 mini. Before August 31, check those sessions and any saved model preferences so you know what will happen when the sign-in path changes.

If your workflow already uses an API key, OpenAI's announcement says the models remain available through the API and API-key-authenticated Codex sessions. The cited sources do not provide additional migration steps or a replacement-model recommendation. (OpenAI Developers on X)

What the sources do and do not establish

OpenAI's announcement establishes the date and the two paths where the models remain available. It does not establish a new default model for ChatGPT-signed-in Codex sessions, whether existing prompts will be automatically migrated, or whether usage limits will change.

Those details are worth checking closer to the deadline if GPT-5.4 is part of a production workflow. Until then, the safe reading is simple: ChatGPT sign-in loses access on August 31, while API-key access remains supported according to the current changelog. (ChatGPT and Codex changelog)

Bottom line

GPT-5.4 and GPT-5.4 mini are scheduled to leave ChatGPT-signed-in Codex sessions on August 31, 2026. API users and Codex users authenticated with an API key are not included in the announced change.

Sources

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Frequently Asked Questions

When will GPT-5.4 and GPT-5.4 mini leave ChatGPT-signed-in Codex sessions?

OpenAI says the models will no longer be available for users signed in with ChatGPT starting August 31, 2026.

Where will GPT-5.4 remain available?

OpenAI says GPT-5.4 and GPT-5.4 mini will remain available on the OpenAI API and in Codex sessions authenticated with an API key.

Does this announcement remove GPT-5.4 from the OpenAI API?

No. The announcement explicitly says the models will remain available on the OpenAI API and in API-key-authenticated Codex sessions.

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