GPT-5.5 Retires From Codex, Migrate to GPT-5.6 Sol
CodexOpenAI announced that GPT-5.5 will retire from ChatGPT, ChatGPT Work, and Codex on October 14, 2026, across consumer, Business, Enterprise, and Edu plans, though the OpenAI API is unaffected. Codex users signed in with a ChatGPT account must switch to GPT-5.6 Sol before the cutoff and update workspace defaults, saved model settings, managed configurations, custom agents, scheduled tasks, and scripts that still reference gpt-5.5. The move continues OpenAI's ongoing GPT-5.x consolidation that already retired GPT-5.4 in August, and it has already drawn pushback from Pro subscribers asking OpenAI to keep GPT-5.5 available as a legacy option inside Codex.
Key Takeaways
- GPT-5.5 will be fully retired from ChatGPT, ChatGPT Work, and Codex on October 14, 2026, across all consumer and business plans, while remaining accessible through the OpenAI API.
- GPT-5.6 Sol is the designated replacement for Codex users signed in with a ChatGPT account, and it has been generally available since July 2026.
- Migration requires manual updates to workspace defaults, saved model settings, managed configurations, custom agents, scheduled tasks, and any scripts still referencing gpt-5.5.
- This is the second GPT-5.x retirement in two months, following GPT-5.4 and GPT-5.4 mini's retirement from Codex on August 31, 2026.
- Some Pro subscribers are pushing back, reporting that GPT-5.6 Sol over-reasons and struggles with basic tool-calling on routine coding tasks compared to GPT-5.5.
- A community feature request is asking OpenAI for 90 days' notice on future model retirements and evaluation against real-world workflows rather than benchmark scores alone.
Sources & Mentions
1 external resource covering this update
GPT-5.5 Set to Retire From Codex and ChatGPT
On October 14, 2026, OpenAI will retire GPT-5.5 from ChatGPT, ChatGPT Work, and Codex across every plan tier, including consumer, Business, Enterprise, and Edu accounts. The retirement does not touch the OpenAI API, so anyone calling gpt-5.5 directly through the API can keep doing so; the change only affects the model as it is surfaced inside ChatGPT and Codex.
What Codex Users Need to Do
For anyone using Codex with ChatGPT sign-in, OpenAI is directing a migration to GPT-5.6 Sol, the flagship tier of the GPT-5.6 family that has been generally available since July 2026. Before the October 14 deadline, Codex users need to update several places where a model choice can be pinned: workspace defaults, saved model settings, managed configurations, custom agents, and scheduled tasks. Any scripts that still hard-code gpt-5.5 as the selected model will also need to be updated, since automated workflows will otherwise fail once the retirement takes effect. OpenAI pointed users to its GPT-5.5 retirement guide and its workspace model availability documentation for migration steps.
Part of a Broader Model Consolidation
This is not the first retirement in the GPT-5.x line this quarter: GPT-5.4 and GPT-5.4 mini were retired from Codex on August 31, 2026, with saved configurations rolled onto gpt-5.6-terra and gpt-5.4-mini onto gpt-5.6-luna respectively. The GPT-5.5 retirement follows the same pattern, moving remaining GPT-5.5 traffic onto the newer GPT-5.6 Sol tier as OpenAI narrows the number of model snapshots it has to support in production.
Developer Pushback
The announcement has already generated friction in the OpenAI Developer Community. One Pro subscriber opened a thread asking OpenAI to keep GPT-5.5 available as a legacy option in Codex, arguing that GPT-5.6 Sol "frequently over-reasons" and adopts indirect workarounds on routine coding tasks compared to GPT-5.5, and citing GitHub issues where GPT-5.6 variants stumbled on basic operations like web search and tool-calling. The thread also asked OpenAI to give at least 90 days' notice before future retirements and to evaluate replacement models against full real-world workflows rather than benchmark scores alone. As of this writing, OpenAI has not announced any change to the October 14 retirement date.