OpenAI ChatGPT Plus OAuth succeeds but third-party Codex calls return 429 quota exceeded
Fix OpenAI API 429 quota exceeded error for ChatGPT Plus subscribers making third-party API calls despite having active subscription Includes evidence for OpenAI API troubleshooting demand.
Source-backedLast updated May 15, 20261 sourceNeeds local verification
ChatGPT Plus OAuth succeeds but third-party Codex API calls return 429 quota exceeded — not an OAuth login failure, affects paying Plus subscribers
Quick fix
Reduce request pressure, check quota or plan limits, and retry with backoff instead of immediate repeated requests.
Updated
Verification status
Source-backed
Evidence
1 public source URL
Before you change production
This page includes public source URLs in the imported troubleshooting record. Compare those references with your version and environment before applying changes.
Reproduce the smallest failing action and save non-secret logs before changing configuration.
Check versions for OpenAI API, related SDKs, package managers, CI runners, and hosting providers.
Change one setting or dependency at a time, then rerun the same failing command or request.
Avoid destructive commands, credential rotation, billing changes, or security relaxations without a rollback plan.
What this error means
ChatGPT Plus OAuth succeeds but third-party Codex API calls return 429 quota exceeded — not an OAuth login failure, affects paying Plus subscribers is a OpenAI API failure pattern reported for developers trying to fix openai api 429 quota exceeded error for chatgpt plus subscribers making third-party api calls despite having active subscription. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.
Why this happens
Reported on openai/openai-python#2951 (2026-03-10). Paying ChatGPT Plus subscribers receive 429 quota exceeded when making third-party Codex API calls. OAuth authentication succeeds but API quota is incorrectly applied. Direct billing/subscription impact. Category: OpenAI API (quota/billing error).
Common causes
Reported on openai/openai-python#2951 (2026-03-10). Paying ChatGPT Plus subscribers receive 429 quota exceeded when making third-party Codex API calls. OAuth authentication succeeds but API quota is incorrectly applied. Direct billing/subscription impact. Category: OpenAI API (quota/billing error).
Quick fixes
Confirm the exact error signature matches ChatGPT Plus OAuth succeeds but third-party Codex API calls return 429 quota exceeded — not an OAuth login failure, affects paying Plus subscribers.
Check the OpenAI API account, local tool state, and provider configuration involved in the failing workflow.
Reduce request pressure, check quota or plan limits, and retry with backoff instead of immediate repeated requests.
Platform/tool-specific checks
Verify the command, editor, extension, or API client that produced the error.
Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
Avoid deleting credentials, local model data, or project settings until the failing scope is clear.
Step-by-step troubleshooting
Capture the exact error message and the command, editor action, or request that triggered it.
Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
Review the source evidence below and compare it with your environment.
Apply one change at a time and rerun the smallest failing action.
Keep the working fix documented for the team or deployment environment.
How to prevent it
Keep provider/tool configuration documented.
Record non-secret diagnostics such as tool version, provider name, model name, and command path.
Add a lightweight check before CI or production workflows depend on the tool.
Diagnostic flow for this page
Match ChatGPT Plus OAuth succeeds but third-party Codex API calls return 429 quota exceeded — not an OAuth login failure, affects paying Plus subscribers exactly before applying the quick fix.
Compare the failing environment with OpenAI API versions, account scope, provider settings, and deployment context.
Check the listed common causes in order, starting with the cause that best matches your logs.
Use the evidence status below to decide whether to confirm against public sources or official documentation.
Apply one reversible change, rerun the smallest failing action, and keep rollback notes.