GitHub Deprecates Gemini 2.5 Pro and Gemini 3 Flash Across Copilot
The retirement reaches every Copilot surface, while enterprise administrators may need to enable the suggested replacement models.
GitHub deprecated Gemini 2.5 Pro and Gemini 3 Flash across GitHub Copilot on July 31, 2026. The change applies to Copilot Chat, inline edits, ask and agent modes, and code completions, so it affects both interactive use and workflows that select either model explicitly.
What changed
GitHub now points customers from Gemini 2.5 Pro to Gemini 3.1 Pro in preview, and from Gemini 3 Flash to Gemini 3.6 Flash. The company is asking users to update workflows and integrations to supported models rather than relying on the retired options.
The deprecation is already in effect. GitHub says administrators do not need to take action to remove the two retired models. That does not mean every replacement will appear automatically for every organization, however. Copilot Enterprise administrators may need to enable the suggested alternatives through model policies before users can select them.
For enterprise teams, that makes the migration partly a governance task. An integration can be updated to name a supported model while still failing for a user whose organization has not enabled that model. GitHub directs administrators to check individual Copilot settings and confirm that the relevant policy is enabled; an enabled model should then appear in the Copilot Chat selector in Visual Studio Code and on GitHub.com.
Why it matters
Model retirement can break assumptions embedded in prompts, automations, documentation and internal support material even when the surrounding Copilot product remains available. Teams that selected one of the two Gemini models for a particular latency, output style or approval process now need to test the suggested successor in their own workload.
The replacement path is also uneven. Gemini 3.1 Pro is identified as a preview, while Gemini 3.6 Flash is presented without that qualifier. Organizations that restrict preview models may therefore need a different migration decision for former Gemini 2.5 Pro users than for former Gemini 3 Flash users.
What remains uncertain
GitHub's notice does not explain why the two models were deprecated, whether existing saved configurations are rewritten automatically, or whether the suggested alternatives behave equivalently in every Copilot surface. It also does not publish migration test results. The announcement establishes the new product state and recommended destinations, but teams should verify behavior before treating the swap as transparent.
Status
Confirmed. GitHub announced the deprecations in its official changelog. Internal confidence is medium because the operational details come from one first-party source and have not been independently corroborated.
Sources
Update note: Last reviewed 2026-07-31. We will revise this post if GitHub changes the replacement guidance or clarifies migration behavior.
Sources
Drafted with AI assistance from source briefs; reviewed for citation completeness and label accuracy.