I’ve been experiencing an unexpected and significant spike in Gemini API billing starting around April 7, 2026, despite my actual API usage decreasing during the same period.
My setup:
Model: gemini-3-flash-preview
Google Search Grounding is enabled on all requests
No changes to code, traffic, or configuration around the time the spike began
What I observed:
Daily costs jumped from a baseline of roughly a few thousand KRW to ~₩150,000–200,000 per day around April 7–10
Total cost for April 5 – April 11: ₩694,000
API request count did not increase — it actually slightly decreased
The cost chart shows a clear and sudden spike that does not correlate with request volume
I’ve reviewed my code and the only model being called is gemini-3-flash-preview with GoogleSearch grounding enabled on every request. There were no deployments or config changes around April 7.
Has anyone else seen a similar pattern recently? Is there any known billing issue or model update for gemini-3-flash-preview around early April 2026?
Any guidance from the Google team would be appreciated.
Me and other devs had a similar issue since march 16th. It’s been almost a month and even though we asked Google team for help several times , we didn’t get a clear answer and it still hasn’t been fixed .
So I have to pay 4x as much as before. I don’t know what to do
