On October 23, 2026 (UTC calendar day; OpenAI’s deprecations page does not give a clock time), OpenAI shut down access to a set of older API model snapshots listed under the April 22, 2026 notice “Legacy GPT model snapshots.” The page says the goal is to improve reliability and make it easier for developers to choose the right models. We have not called these endpoints to verify that shutoff behavior matches the documentation.
This article covers only that October 23, 2026 batch from the 2026-04-22 notice. It does not re-list the July 23, 2026 past shutdown group, and it does not expand other upcoming deprecations on the same page (for example later GPT-4o family dates).
Main snapshots shutting down October 23, 2026
| Model snapshot | Aliases / related IDs (if listed) | Substitute model |
|---|---|---|
| gpt-3.5-turbo-0125 | gpt-3.5-turbo, gpt-3.5-turbo-completions | gpt-5.6-terra |
| gpt-4-0613 | gpt-4, gpt-4-0613-completions, gpt-4-completions | gpt-5.6-sol |
| gpt-4-1106-preview | — | gpt-5.6-sol |
| gpt-4-turbo | gpt-4-turbo-2024-04-09, gpt-4-turbo-completions | gpt-5.6-sol |
| gpt-4.1-nano | gpt-4.1-nano-2025-04-14 | gpt-5.6-luna |
| gpt-4o-2024-05-13 | — | gpt-5.6-sol |
| gpt-image-1 | — | gpt-image-2.5-sunburst or gpt-image-2.5-flare |
| o1-2024-12-17 | o1 | gpt-5.6-sol |
| o1-pro-2025-03-19 | o1-pro | gpt-5.6-sol (reasoning.mode: pro) |
| o3-mini-2025-01-31 | o3-mini | gpt-5.6-sol |
| ft-o4-mini-2025-04-16 | — | gpt-5.6-terra |
| o4-mini-2025-04-16 | o4-mini | gpt-5.6-terra |
Fine-tuned versions also shutting down October 23, 2026
| Model snapshot | Recommended replacement base model |
|---|---|
| ft-gpt-3.5-turbo | gpt-5.6-terra |
| ft-gpt-4 | gpt-5.6-sol |
| ft-gpt-4.1-nano-2025-04-14 | gpt-5.6-luna |
| ft-babbage-002 | gpt-5.6-terra |
| ft-davinci-002 | gpt-5.6-terra |
If your code still pins any of the IDs above—including aliases such as gpt-4, gpt-4-turbo, o1, or o4-mini—OpenAI’s table is the migration map to use. We have not re-tested request routing, error messages, or fine-tune inference after the date.
Same-day and nearby model-shutdown context on DigIntoAI: Gemini API Deep Research Pro preview also shuts down October 23, and GPT-5.5 leaves Codex on October 14—what to switch to.
