OpenAI announced GPT-5.5 would retire from ChatGPT, ChatGPT Work and Codex on October 14

Archive entry: this covers an event from September 14, 2026, and we published it on November 8, 2026. The details come from sources dated at the time and may have changed since.

On September 14, 2026, OpenAI announced in its ChatGPT and Codex changelog that GPT-5.5 would retire from ChatGPT, ChatGPT Work and Codex on all plans one month later, on October 14, 2026. The retirement did not apply to the OpenAI API, where GPT-5.5 stayed available.

What changed

• GPT-5.5 was scheduled to retire from ChatGPT, ChatGPT Work and Codex on all plans on October 14, 2026.
• In Codex, the retirement took effect on October 14, 2026 at noon PDT (19:00 UTC) for ChatGPT sign-in.
• API usage and Codex sessions authenticated with an API key were not affected.
• The replacement model in Codex was gpt-6.1-sol.

What it means for builders

Subscription users lost GPT-5.5 one month after the GPT-6 launch, so workflows tuned to it had to move. In Codex, the move was to gpt-6.1-sol, and it applied to sessions that signed in with ChatGPT.

Builders who used GPT-5.5 through the OpenAI API, or ran Codex sessions with an API key, saw no change. The notice gave a month between the announcement and the cutover, so the change was scheduled rather than a surprise.

Sources

• ChatGPT & Codex changelog: GPT-5.5 retires from ChatGPT, ChatGPT Work, and Codex on October 14 (OpenAI, September 14, 2026, official)

Written with AI assistance, strictly from the sources listed above. Before it went live, automated checks verified its dates, sources and every language edition.