GPT-5.5 retired from ChatGPT, ChatGPT Work, and Codex on 14 October 2026

As of 14 October 2026 at noon PDT, OpenAI has retired GPT-5.5 from ChatGPT, ChatGPT Work, and Codex across every plan tier, including consumer, Business, Enterprise, and Edu. The model itself has not been deleted. If you access it via the OpenAI API with an API key, nothing changes for you. But if any of your setups reference GPT-5.5 by name inside ChatGPT’s surfaces, those references stopped working on that date.

This is a product-level retirement, not a full deprecation. OpenAI has followed the same pattern before: GPT-4o was retired from ChatGPT on 13 February 2026 while remaining available through the API, and the GPT-5.1 model family left ChatGPT on 11 March 2026 under identical terms. GPT-5.5 is the latest to follow that path.

What actually broke on 14 October 2026

For the majority of ChatGPT users who simply open the app and start chatting, nothing will feel different. ChatGPT will route you to a supported model automatically.

The problem hits people who have done any of the following:

• Pinned GPT-5.5 in workspace or account settings. Those pinned preferences now fail silently or throw an error, depending on the client.
• Built a custom GPT that selects GPT-5.5 as its base model. The custom GPT will not work until you open its configuration and switch to a supported model.
• Set up scheduled tasks that call GPT-5.5 by name. Those tasks will fail on their next run.
• Written Codex scripts with gpt-5.5 hardcoded. Any Codex session authenticated through ChatGPT (not an API key) will no longer execute those scripts as written.

If you are a developer using the OpenAI API directly with an API key, you are unaffected. GPT-5.5 continues to respond to API calls, and Codex sessions authenticated via API key are also unaffected.

One more date worth noting: GitHub removes GPT-5.5 from all Copilot experiences on 19 October 2026, five days after the ChatGPT retirement.

Which model should you migrate to

OpenAI’s recommendation depends on your plan and what you were using GPT-5.5 for.

For most ChatGPT and ChatGPT Work users on Plus, Pro, Business, Enterprise, or Edu plans, the recommended replacement is GPT-6.1 Sol (gpt-6.1-sol). It was announced at DevDay 2026 on 29 September 2026 and is available across those tiers. OpenAI describes it as delivering performance close to GPT-6 Astra at roughly one-fifth of Astra’s token price.

For Codex users, OpenAI specifically recommends switching to GPT-5.6 Sol or GPT-6 Astra. If you are coming from GPT-5.5 and want a more gradual step up, GPT-5.6 Terra is also documented as a natural starting point. GPT-6.1 Sol’s new Ultrafast mode is available in both Codex and ChatGPT Work, which speeds up token generation noticeably for iterative coding tasks.

A quick look at the numbers helps frame the choice:

Model	Tool-use score	Speed	Price (input / output per 1M tokens)
GPT-6 Astra	95.9%	54.0 tok/sec	Higher
GPT-5.6 Sol	83.3%	64.7 tok/sec	Mid
GPT-6.1 Sol	Near-Astra	Ultrafast mode	$2 / $10
GPT-5.5 (retired from ChatGPT)	82.7% on Terminal-Bench 2.0	,	$5 / $30

GPT-6.1 Sol is notably cheaper than GPT-5.5 was on the API, so teams that do migrate may find the economics improve at the same time as capability.

For Codex CLI users, check your version: GPT-5.6 Sol requires at least Codex CLI 0.144.0, and GPT-6 Astra requires 0.153.0. If you are on an older version, update before you migrate your scripts.

How to migrate your setup

The steps are straightforward, but you do need to go through them methodically if you have built anything on top of GPT-5.5.

1. Workspace and account settings. Open your ChatGPT or ChatGPT Work settings, find any saved model preferences, and update them to GPT-6.1 Sol or whichever replacement suits your plan.

2. Custom GPTs. Go into the builder for each custom GPT that uses GPT-5.5 as its base. Change the model selection and republish. Anyone using that GPT will then be on the updated version.

3. Scheduled tasks. Review any automations or scheduled tasks that specify gpt-5.5 in their configuration. Update the model identifier to gpt-6.1-sol or another supported model.

4. Codex scripts. Find every place in your scripts where gpt-5.5 is hardcoded and replace it. If you are moving to GPT-6 Astra, verify your Codex CLI version first.

5. Managed configurations and agents. If your organisation manages ChatGPT settings centrally, the administrator will need to push updated model selections to any managed configurations that reference GPT-5.5.

A note for API developers

Nothing changes for you on 14 October 2026. GPT-5.5 continues to respond to API calls, and there is no announced end-of-life date for API access at this point. That said, given OpenAI’s track record of eventually deprecating models fully, it is worth planning your migration timeline rather than assuming API availability is permanent. GPT-6.1 Sol at $2 input / $10 output per million tokens is also considerably cheaper than GPT-5.5’s API pricing of $5 / $30, so there is a practical financial case for moving sooner rather than later.

The short version

GPT-5.5 left ChatGPT, ChatGPT Work, and Codex on 14 October 2026. If you just use ChatGPT to chat, you will not notice anything. If you have pinned it, built on it, or scripted it, those configurations are now broken and need updating. Switch to GPT-6.1 Sol for most ChatGPT and ChatGPT Work use cases, or to GPT-5.6 Sol or GPT-6 Astra for Codex. API access is unaffected. The migration itself is not technically difficult, but it does require you to audit everything that had GPT-5.5 wired in by name.