Upcoming August 2026 model deprecations in GitHub Copilot

GitHub announced Upcoming August 2026 model deprecations in GitHub Copilot on the GitHub Changelog and The GitHub Blog. The company will deprecate a listed set of models on September 1st, 2026, and the change applies across all GitHub Copilot experiences rather than a single surface.

The deprecation covers Copilot Chat, inline edits, ask and agent modes, and code completions. That span means the same model retirement hits conversational help, in-editor rewrites, agent-style multi-step work, and completion suggestions together, so product behavior is not limited to one interaction path.

For engineers and builders, any workflow pinned to a soon-to-be-retired model in those surfaces will need a replacement before September 1st, 2026. Teams that hard-code model choice in org policy, IDE settings, or agent prompts should treat the changelog list as the authoritative cutover inventory and retest affected flows against whatever remains supported.

In market terms, this is a vendor-side model lifecycle event inside a widely used coding assistant, not a new feature launch. Competitors that already force model switches or multi-model routing will look familiar to teams that have lived through similar retirements; the practical difference here is GitHub applying one date across chat, edits, agent modes, and completions at once.

Watch the official model list and any successor mappings GitHub publishes before September 1st, 2026, then migrate defaults and shared configs early enough to catch regressions in agent mode and completion quality. Confirm that org-level model restrictions still resolve to supported options after the cutover.