GitHub Copilot to Drop Claude Sonnet 4 on May 1 — Migrate to Sonnet 4.6 Now
GitHub has officially announced that Claude Sonnet 4 will be deprecated across all Copilot experiences on May 1, 2026. The cutover covers the full breadth of Copilot integrations: Copilot Chat, inline edits, ask mode, agent mode, and code completions. The recommended migration path is Claude Sonnet 4.6. For individual users, the transition is relatively low-friction once Sonnet 4.6 is available in the model selector — but enterprise administrators face an additional step. They must proactively enable Sonnet 4.6 through Copilot model policy settings before May 1; the model will then appear in Copilot Chat's model selector in VS Code and on github.com. GitHub will handle removal of the deprecated model automatically after the cutover date.
Any team relying on Claude Sonnet 4 through GitHub Copilot has a 30-day window to act. Enterprise admins in particular should verify policy settings now rather than discover a silent model change mid-sprint. For developers running multi-model setups where Copilot operates alongside Codex or other agents, now is also a good time to audit which model each workflow is actually calling.