OpenAI to retire GPT-5.4 in Codex Aug.31

OpenAI said in a Help Center update that Codex will retire GPT-5.4 and GPT-5.4 mini on August 31, 2026, for users who sign in with ChatGPT accounts. The company directed those users to move to GPT-5.6 Terra and GPT-5.6 Luna instead. (help.openai.com) The notice appears in OpenAI’s Codex rate card and in a separate Help Center article on using Codex with a ChatGPT plan. The change is narrower than a full model shutdown. OpenAI said the retirement applies to Codex access for users signed in with ChatGPT, while “OpenAI API access and Codex use with your own API key are not affected.” That means developers using Codex through a ChatGPT-linked workflow face the deadline, but API-based usage is not being retired by this notice. (help.openai.com) ### Which users are actually affected by the August 31 change? OpenAI’s wording names “users signed in with ChatGPT” as the group affected inside Codex. (help.openai.com) The Help Center article on ChatGPT-plan access repeats that GPT-5.4 and GPT-5.4 mini “will no longer be available in Codex when you sign in with your ChatGPT account” after August 31, 2026. The same articles carve out a separate path for developers using their own API credentials. OpenAI said Codex use with a user’s own API key is not affected, drawing a line between ChatGPT-account access and API-key-based access. (help.openai.com) ### What is OpenAI telling people to use instead? The Help Center gives a direct one-for-one replacement. OpenAI said users should “Use GPT-5.6 Terra instead of GPT-5.4 and GPT-5.6 Luna instead of GPT-5.4 mini.” The companion article aimed at ChatGPT-plan users repeats the same instruction. (help.openai.com) The guidance is framed as immediate migration advice rather than a later recommendation. In the ChatGPT-plan article, OpenAI tells users to replace GPT-5.4 with GPT-5.6 Terra, indicating the company wants developers to begin moving code-generation workloads before the August 31 cutoff. (help.openai.com) ### Where did OpenAI publish the retirement notice? The retirement notice appears in OpenAI’s “Codex rate card” Help Center article. That page says it includes credits-per-1-million-token pricing information and places the retirement language above the rate table. (help.openai.com) A second Help Center page, “Using Codex with your ChatGPT plan,” repeats the same retirement date and replacement models. That article also describes Codex as “an AI agent that helps you write, review, and ship code,” placing the model change in the context of developer workflows. (help.openai.com) ### Is this part of a broader OpenAI model-retirement pattern? OpenAI’s model release notes show the company has continued retiring older models in ChatGPT during 2026. The release notes list prior retirements for GPT-4.5, OpenAI o3 and earlier GPT-5.1 variants, and say those changes were made to make room for newer models. (help.openai.com) The same release notes and Help Center pages also show GPT-5.6 is already being rolled out in ChatGPT under the “Sol” branding, while the Codex retirement notice points Codex users to the Terra and Luna variants. (help.openai.com) OpenAI said GPT-5.6 availability can vary by eligible plan. ### What should Codex users do before August 31? August 31, 2026 is the date OpenAI lists for removal of GPT-5.4 and GPT-5.4 mini from Codex for ChatGPT-signed-in users. The practical next step in OpenAI’s own guidance is to switch those workflows to GPT-5.6 Terra and GPT-5.6 Luna now. (help.openai.com) The Help Center points users to migration guidance and rate-card information in the same Codex support materials. OpenAI’s published note says API users and people running Codex with their own API key do not need to make that specific access change under this retirement notice. (help.openai.com 1) (help.openai.com 2)