Free plan + Codex credits, but GPT-5.6 Sol is still blocked — what’s the point of the credits?

Codex
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1

I’m honestly pretty frustrated with how Codex model access and credits are currently working.

I’m on the Free ChatGPT plan, and I have Codex credits available. I installed the latest Codex CLI (v0.151.0) and tried to use GPT-5.6 Sol directly:

codex -m gpt-5.6-sol

Codex recognizes the model, but the server returns:

The 'gpt-5.6-sol' model is not supported when using Codex with a ChatGPT account.

Sol also does not appear in the /model list.

What I don’t understand is this:

If I have credits that can be used for Codex, why can’t I spend those credits on Sol?

I completely understand having different limits for Free vs paid plans. What feels confusing is having a credit balance but being unable to use those credits for a model that Codex itself recognizes.

I’ve also seen Reddit posts from users saying they can use Sol with credits, which makes the situation even more confusing. Is Sol access based on the subscription plan, account rollout, or something else?

Could someone from OpenAI please clarify:

  • Are GPT-5.6 Sol and Free-plan Codex credits completely incompatible?
  • Are credits only usable for models already included with your plan?
  • Is this a temporary rollout/entitlement issue?
  • If Sol requires Plus or higher regardless of credits, why isn’t that made clearer in the Codex UI?

I’m not asking for free unlimited access. I already have credits and I’m willing to spend them. I just want to understand why those credits can’t be used for the model I want.

The current experience feels unnecessarily confusing.

Would appreciate an official clarification from OpenAI staff or anyone who has figured this out.

2

Did you try contacting OpenAI support directly via the button at the bottom of the pages in their Help Center? https://help.openai.com/en/

Don’t hesitate to ask than a human responses, even if that’s first the AI that answers, it has to write that it has been escalated to a support specialist.

3

FYI should be available via an API account from Tier 1 at https://platform.openai.com.

This is a separate account to your ChatGPT account though.

However you can use your API account keys with Codex too.

4

An OpenAI ChatGPT FAQ page notes

https://help.openai.com/en/articles/20001354-gpt-56-in-chatgpt

GPT-5.6 Sol and a new reasoning slider are rolling out to eligible paid plans. GPT-5.6 Luna is becoming the default model for Free and Go users. GPT-5.6 Sol powers Instant, Medium, High, and Extra High on eligible paid plans, while GPT-5.6 Sol Pro powers Pro.

5

yeh but can’t use the credits that i have for those can I?

6

From what I understand, your reply is about regular ChatGPT chat, while the question was about access to the Sol model in Work/Codex.