GitHub Copilot Drops Gemini 2.5 Pro and Gemini 3 Flash on July 31

GitHub retired two Gemini models from all GitHub Copilot experiences on July 31, 2026. Gemini 2.5 Pro and Gemini 3 Flash are now deprecated across Copilot Chat, inline edits, ask and agent modes, and code completions. GitHub points users to Gemini 3.1 Pro (Preview) and Gemini 3.6 Flash as the respective replacements. Copilot Enterprise administrators may need to take action in their settings before the new models become available to their teams.

What happened

Detail	Value
Deprecation date	July 31, 2026
Deprecated: Gemini 2.5 Pro	Replace with Gemini 3.1 Pro (Preview)
Deprecated: Gemini 3 Flash	Replace with Gemini 3.6 Flash
Affected surfaces	Copilot Chat, inline edits, ask mode, agent mode, code completions

GitHub confirmed the deprecation on the same day it took effect, giving teams no runway to plan. Both models were removed from every GitHub Copilot surface simultaneously, including the model selector visible in VS Code and on github.com.

Why it matters

Any workflow, extension, or integration that explicitly references Gemini 2.5 Pro or Gemini 3 Flash by name will stop working or silently fall back to a different model. That includes CI pipelines using Copilot agent mode, custom VS Code setups, and any enterprise policy that pinned a specific model.

The replacement models are a generation newer. Gemini 3.1 Pro (Preview) replaces the outgoing Pro tier, while Gemini 3.6 Flash takes over from Gemini 3 Flash on the faster, lighter-weight side. Preview labels on models like Gemini 3.1 Pro signal that the model is still subject to change, which is worth keeping in mind for production integrations.

Enterprise administrators face an extra step. According to GitHub, Copilot Enterprise admins may need to explicitly enable the new models through model policies in Copilot settings before team members can see or select them. Without that change, users may find the replacement models missing from their selector entirely.

What to do about it

1. Check any saved VS Code settings, .github/copilot config files, or CI scripts that reference gemini-2.5-pro or gemini-3-flash by model ID and update them to the replacement model IDs.
2. If you run a Copilot Enterprise account, open Copilot settings, navigate to model policies, and verify that Gemini 3.1 Pro (Preview) and Gemini 3.6 Flash are enabled for your organisation.
3. After enabling, confirm the models appear in the Copilot Chat model selector in VS Code and on github.com before rolling out to your team.
4. Contact your GitHub account manager if you are an Enterprise customer and run into access or policy issues.

Our take

Same-day deprecations with no advance notice are a recurring problem across AI tooling, and this one fits the pattern well. GitHub gave no migration window, so anyone running automated workflows that pinned these models got a surprise on July 31.

The model naming here is also worth flagging. Jumping from “Gemini 2.5 Pro” to “Gemini 3.1 Pro (Preview)” and from “Gemini 3 Flash” to “Gemini 3.6 Flash” suggests Google’s versioning is moving fast enough that even minor releases obsolete the previous generation quickly. If you are building on top of Copilot as part of a broader AI integration for your business, avoid hardcoding model names wherever the API or config lets you use an alias or a “latest stable” pointer instead. It will save you from chasing these deprecations every few months.

We have covered a similar situation with GitHub Models being retired on July 30, just one day before this change. The timing suggests GitHub is doing broader model housekeeping across its platform right now. If you have not audited your Copilot setup recently, this week is a good time to do it.

Source: GitHub Changelog