A 429 error when calling the Gemini-2.5-pro API despite tier 1

Hello, I am encountering a 429 error when calling the Gemini-2.5-pro API. I can confirm that my API is on the paid Tier 1 level and was running well a week ago. The 429 error suddenly started occurring on June 24th. It appears that Google is defaulting to the free tier.

got status: 429 . {“error”:{“code”:429,“message”:“You exceeded your current quota. Go to https://aistudio.google.com/apikey to upgrade your quota tier, or submit a quota increase request in Rate limits  |  Gemini API  |  Google AI for Developers”:

What worked for me was to unset the GEMINI_API_KEY environment variable and authenticate via gcloud oauth (on VM it would be service account, on CI worload identity).

When I tried to use the GEMINI_API_KEY I couldn’t specify a billing project, so I got the free tier rate limits. Authenticating directly lets me configure the project as I would other gcloud resources.

Hi @user2159,

Welcome to the Forum,

Please follow the below instructions to troubleshoot:

Go to GCP console and click “APIs & Services”. Under Metric, search and select “Generative Language API”.. Under “Quotas & System Limits” tab, check for “Current Usage percentage”..

If it reaches 100%, then you have reached your quota limits and hence the 429 Error.

If you think that there is any discrepancy, please DM me with a clear entire error message and Project ID to help us investigate further.

Thank you!

Thank you for your help. The API calls suddenly returned to normal about 2 hours ago. I think this might have been a minor bug on Google’s end.