›_ Codex Issues
Codex Issues / #14735

gpt-5.3-codex model not supported in Codex CLI when authenticated with ChatGPT Plus

Resolved 💬 14 comments Opened Mar 15, 2026 by pavelbe Closed Jun 2, 2026
💡 Likely answer: A maintainer (github-actions[bot], contributor) responded on this thread — see the highlighted reply below.

What version of Codex CLI is running?

codex-cli 0.114.0

What subscription do you have?

ChatGPT Plus

Which model were you using?

gpt-5.4 (previously working), currently falling back to gpt-5.2

What platform is your computer?

Windows 11 with WSL2 (Ubuntu)

What terminal emulator and version are you using (if applicable)?

Windows Terminal running WSL Ubuntu

What issue are you seeing?

When using Codex CLI with a ChatGPT Plus account, the CLI returns the following error:

"The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account."

Environment:

  • Codex CLI version: 0.114.0
  • OS: Windows 11 with WSL2 (Ubuntu)
  • Authentication: ChatGPT account login
  • Plan: ChatGPT Plus

Important context:
The model gpt-5.4 worked correctly until yesterday with the same setup.
Today the CLI started returning the error above and appears to route requests to gpt-5.3-codex which is not supported for ChatGPT accounts.

As a workaround I had to switch to gpt-5.2 to continue using Codex CLI.

What steps can reproduce the bug?

  1. Install Codex CLI
  2. Login using ChatGPT account authentication
  3. Run Codex CLI normally
  4. The CLI attempts to use gpt-5.3-codex
  5. The CLI returns the error:

"The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account."

Uploaded thread:
019cf02c-4f18-78c0-817a-3db5c82ed772

What is the expected behavior?

Codex CLI should either:

  1. Allow the gpt-5.3-codex model when using a ChatGPT Plus account, or
  2. Automatically select a supported default model instead of failing.

Previously gpt-5.4 worked correctly with the same setup.

Additional information

I noticed that multiple GitHub issues report the same error and were closed as duplicates (for example #14306 referencing #14331).
However the issue still occurs in Codex CLI version 0.114.0.

View original on GitHub ↗

14 Comments

github-actions[bot] contributor · 4 months ago

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

  • #14306
  • #14412
  • #14190
  • #14181
  • #14331

Powered by Codex Action

etraut-openai contributor · 4 months ago

Please refer to this comment.

Gieted · 4 months ago

@etraut-openai I'm having the same issue, despite having a Plus subscription, I cannot use gpt-5.4 nor gpt-5.3-codex inside Codex CLI or Codex desktop app.

talhaayyubi · 4 months ago

@etraut-openai I'm having the same issue as reported above. I'm on a paid Plus plan but can't access gpt-5.4. It keeps falling back to gpt-5.2 or gpt-5 codex based agent. I followed the steps you suggested in your comment on #14331 . Logged out and logged back in, deleted the models cache file, and relaunched. First tried this on the CLI (0.114.0), then upgraded to 0.115.0, and subsequently tried the Codex macOS desktop app as well. No success, still the same result across all of them.

cosmo-drama · 2 months ago

i'm also still running into this, followed all steps: logged out, quit app, restarted, deleted models cache file, upgraded to latest (0.130.0). I'm on a paid plus account. 019e0f86-01ba-7ba1-8a64-5be8acfcd285

ad-borges · 1 month ago

same here. Feedback ID: 019e841d-70a4-7fa1-9cf2-50c51b914d2b

your-diary · 1 month ago

feedback id: 019e85ed-b810-74c1-a76d-76da5e11b995

I suddenly started having this issue today.

{
    "type": "error",
    "status": 400,
    "error": {
        "type": "invalid_request_error",
        "message": "The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account."
    }
}

I believe I have a valid Plus plan.
I used to successfully using the model for months.

Agiras-art · 1 month ago

I am experiencing a similar issue with Codex in VS Code Remote WSL.

Environment:

  • ChatGPT plan: ChatGPT Plus
  • IDE: VS Code with WSL
  • Codex CLI version tested: v0.136.0
  • Project directory: WSL project folder
  • Authentication method: ChatGPT account, not API key

Issue:
The VS Code Codex model dropdown does not show gpt-5.3-codex. It only shows models such as GPT-5.5, GPT-5.4, and GPT-5.4-Mini.

I tried setting the model manually in ~/.codex/config.toml:

model = "gpt-5.3-codex"
model_reasoning_effort = "medium"

The CLI UI initially shows:

model: gpt-5.3-codex medium

However, when Codex actually sends a request, it fails with:

{
  "type": "error",
  "status": 400,
  "error": {
    "type": "invalid_request_error",
    "message": "The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account."
  }
}

This is confusing because the model can be entered manually and appears to be accepted by the local CLI/config, but it is rejected only after the request is sent. Also, the IDE dropdown does not clearly explain whether gpt-5.3-codex is unavailable for ChatGPT Plus accounts, unavailable only in the IDE, or unavailable only for ChatGPT-account authentication.

Expected behavior:

  • If gpt-5.3-codex is not supported for ChatGPT Plus / ChatGPT account authentication, the IDE and CLI should clearly hide or disable it and show a clear availability message.
  • If it is supported, it should appear in the VS Code model dropdown and work consistently when selected or configured in config.toml.
  • The documentation or UI should clearly explain which models are available for ChatGPT Plus, Pro, Business, etc., especially for Codex IDE/CLI usage.

Current impact:
I want to use a model that is more suitable for large codebases and multi-file refactoring without using GPT-5.5, because GPT-5.5 consumes my 5-hour Codex usage limit much faster. GPT-5.4-Mini is available, but it is not ideal for large refactors. GPT-5.4 is available, but it is unclear whether it is the intended replacement for gpt-5.3-codex for ChatGPT Plus users.

Please clarify whether gpt-5.3-codex is supposed to be available for ChatGPT Plus users in Codex VS Code/CLI when signed in with a ChatGPT account, and if not, please update the model selector and error messaging to avoid this confusion.

Ionharin · 1 month ago
same here. Feedback ID: 019e841d-70a4-7fa1-9cf2-50c51b914d2b
feedback id: 019e85ed-b810-74c1-a76d-76da5e11b995 I suddenly started having this issue today. { "type": "error", "status": 400, "error": { "type": "invalid_request_error", "message": "The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account." } } I believe I have a valid Plus plan. I used to successfully using the model for months.
I am experiencing a similar issue with Codex in VS Code Remote WSL. Environment: ChatGPT plan: ChatGPT Plus IDE: VS Code with WSL Codex CLI version tested: v0.136.0 Project directory: WSL project folder * Authentication method: ChatGPT account, not API key Issue: The VS Code Codex model dropdown does not show gpt-5.3-codex. It only shows models such as GPT-5.5, GPT-5.4, and GPT-5.4-Mini. I tried setting the model manually in ~/.codex/config.toml: model = "gpt-5.3-codex" model_reasoning_effort = "medium" The CLI UI initially shows: `` model: gpt-5.3-codex medium ` However, when Codex actually sends a request, it fails with: { "type": "error", "status": 400, "error": { "type": "invalid_request_error", "message": "The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account." } } This is confusing because the model can be entered manually and appears to be accepted by the local CLI/config, but it is rejected only after the request is sent. Also, the IDE dropdown does not clearly explain whether gpt-5.3-codex is unavailable for ChatGPT Plus accounts, unavailable only in the IDE, or unavailable only for ChatGPT-account authentication. Expected behavior: * If gpt-5.3-codex is not supported for ChatGPT Plus / ChatGPT account authentication, the IDE and CLI should clearly hide or disable it and show a clear availability message. * If it is supported, it should appear in the VS Code model dropdown and work consistently when selected or configured in config.toml. * The documentation or UI should clearly explain which models are available for ChatGPT Plus, Pro, Business, etc., especially for Codex IDE/CLI usage. Current impact: I want to use a model that is more suitable for large codebases and multi-file refactoring without using GPT-5.5, because GPT-5.5 consumes my 5-hour Codex usage limit much faster. GPT-5.4-Mini is available, but it is not ideal for large refactors. GPT-5.4 is available, but it is unclear whether it is the intended replacement for gpt-5.3-codex for ChatGPT Plus users. Please clarify whether gpt-5.3-codex` is supposed to be available for ChatGPT Plus users in Codex VS Code/CLI when signed in with a ChatGPT account, and if not, please update the model selector and error messaging to avoid this confusion.

They have stopped Plus users from accessing GPT-5.2 and GPT-5.3 Codex.
Source：https://x.com/thsottiaux/status/2059650685948551384

your-diary · 1 month ago

@Ionharin

Source：https://x.com/thsottiaux/status/2059650685948551384
Author: Tibo(@thsottiaux) Codex & ChatGPT @ OpenAI To simplify our Codex compute fleet management, we will be sunsetting GPT-5.2 and GPT-5.3-Codex in Codex on June 2nd when logged in with your ChatGPT account. For free plans, GPT-5.5 will be the default frontier model to build and work with going forward. These models will remain available on our API.

Thank you for the info!
Now I have to use at least gpt-5.4, which is more costly (~ 1.5x) than gpt-5.3-codex...

Nikita-schetko · 1 month ago

Guys, Honestly, this is very disappointing :((

I’m paying for ChatGPT Plus and was using gpt-5.3-codex specifically because it felt like the best model for real coding work in Codex CLI / native app.

Removing it from ChatGPT-authenticated Codex, while keeping it available via API, feels like a downgrade for paid users and makes the product much less predictable :/

Please provide a clear replacement path, not just a “model not supported” error.
Where is the codex 5.5 ???

aipartnerZA · 1 month ago

As of last night, 5.3-codex stopped working for me in Codex CLI on ChatGPT Plus. 5.4 is inferior to 5.3-codex for coding related tasks. I won't be continuing with a ChatGPT subscription if there is no access to Codex level models.

etraut-openai contributor · 1 month ago

The gpt-5.2 and gpt-5.3-codex models have been retired. Please update to gpt-5.4 or gpt-5.5. These models have been trained for coding, so there is no special "codex" variant of these newer-generation models. They are excellent at coding — significantly better than the older-generation models.

linkedbump · 1 month ago

I found the root cause on Windows.

The issue was not fixed by:

  • Reinstalling Codex
  • Logging out and back in
  • Creating new agents

The problem was in:

C:\Users\<username>\.codex\config.toml

My config still contained:

model = "gpt-5.3-codex"

Even after reinstalling the app.

The error was:

The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account

Changing the config to:

model = "gpt-5.5"

fixed the issue immediately.

For anyone looking for the file, you don't need to search manually:

Settings → Configuration → Open config.toml

The desktop app includes a direct link to the configuration file.

It looks like Codex preserves .codex/config.toml across reinstalls, so users may continue trying to use gpt-5.3-codex without realizing it.

Hope this helps someone else.

<img width="2402" height="1223" alt="Image" src="https://github.com/user-attachments/assets/30e31e31-7681-4804-bcc1-2a3addfcaf53" />