---
title: "gemini-2.5-flash on Gemini API retirement date | Since.dev"
description: "gemini-2.5-flash on Gemini API is routed to gemini-3.5-flash-lite on December 1, 2026. Replacement: gemini-3.5-flash-lite."
canonical_url: https://since.dev/calendar/google/gemini-2.5-flash/gemini
last_updated: 2026-11-12
---

# gemini-2.5-flash on Gemini API is routed to gemini-3.5-flash-lite on December 1, 2026

AI model

- **Date:** December 1, 2026 (UTC)
- **Replacement:** `gemini-3.5-flash-lite`
- **Platform:** Gemini API
- **Provider:** [Google](https://since.dev/calendar/google.md)
- **Last checked:** Nov 14, 2026

gemini-2.5-flash

Routes to gemini-3.5-flash-lite December 1, 2026 on Gemini API

In its place: `gemini-3.5-flash-lite`

since.dev/calendar/google/gemini-2.5-flash/gemini

## What changes

Requests keep working, answered by gemini-3.5-flash-lite.

## What works differently on `gemini-3.5-flash-lite`

From its documentation. Moving to it is more than a new model ID.

- The default thinking level is minimal, so a request that does not set thinking_level runs at minimal. To keep the old behavior: for autonomous subagents with tool calls, code execution, or multi-step reasoning, set thinking_level to "medium" or "high". [Source](https://ai.google.dev/gemini-api/docs/whats-new-gemini-3.6)
- temperature, top_p, and top_k are deprecated; the API ignores these parameters and returns an error in future model generations. To keep the old behavior: remove these parameters from all requests. [Source](https://ai.google.dev/gemini-api/docs/whats-new-gemini-3.6)
- Prefilled model turns are no longer supported; if the last non-empty turn in the request is a model turn, the API returns a 400 error. To keep the old behavior: instead of prefilling a model turn, use system_instruction or Structured outputs. [Source](https://ai.google.dev/gemini-api/docs/whats-new-gemini-3.6)
- candidate_count is unsupported in Gemini 3 and later. To keep the old behavior: remove candidate_count from requests. [Source](https://ai.google.dev/gemini-api/docs/whats-new-gemini-3.6)

## Source

[aistudio.google.com](https://aistudio.google.com/docs/deprecations)

> gemini-2.5-flash | June 17, 2025 | December 1, 2026 | gemini-3.5-flash-lite (gemini-2.5-flash is no longer available in Google AI Studio; effective December 1, 2026, API requests to gemini-2.5-flash will automatically route to gemini-3.5-flash-lite)

Data license: [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). From Google's documentation. Quotes are shortened and dates restated.

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[Add to your calendar](webcal://api.since.dev/v1/calendar.ics?provider=google) · [iCal file](https://api.since.dev/v1/calendar.ics?provider=google) · [RSS](https://api.since.dev/v1/calendar.rss?provider=google)

## More from Google

- Nov 19, 2026 · no sooner than · [gemini-3.6-flash on Vertex AI](https://since.dev/calendar/google/gemini-3.6-flash/vertex.md) · Google · AI model · replace with gemini-3.8-flash
- Dec 1, 2026 · [gemini-2.5-pro on Gemini API](https://since.dev/calendar/google/gemini-2.5-pro/gemini.md) · Google · AI model · replace with gemini-3.8-flash
- Dec 3, 2026 · [gemini-omni-1.1-flash on Gemini API](https://since.dev/calendar/google/gemini-omni-1.1-flash/gemini.md) · Google · AI model · replace with gemini-omni-1.2-flash
- Dec 13, 2026 · no sooner than · [gemini-live-2.5-flash-native-audio on Vertex AI](https://since.dev/calendar/google/gemini-live-2.5-flash-native-audio/vertex.md) · Google · AI model · replace with gemini-3.8-live
- Dec 18, 2026 · no sooner than · [gemini-2.5-pro-preview-tts on Gemini API](https://since.dev/calendar/google/gemini-2.5-pro-preview-tts/gemini.md) · Google · AI model · replace with gemini-3.8-flash-tts or gemini-3.8-flash-lite-tts
- Dec 18, 2026 · no sooner than · [gemini-2.5-flash-preview-tts on Gemini API](https://since.dev/calendar/google/gemini-2.5-flash-preview-tts/gemini.md) · Google · AI model · replace with gemini-3.8-flash-tts or gemini-3.8-flash-lite-tts

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