GitHub announced general availability of Claude Sonnet 5.5 in GitHub Copilot on September 28, 2026. The practical question for Copilot users is where they can select the model and whether an organization policy permits it. GitHub says the rollout is gradual, so an eligible subscriber may not immediately see it in the model picker. This Copilot availability announcement is separate from Anthropic’s description of the model itself. Source
Eligible plans and places to select it
GitHub lists Copilot Pro, Pro+, Max, Business, and Enterprise as eligible plans. Sonnet 5.5 appears in the model picker across supported tools including Visual Studio Code, Visual Studio, Copilot CLI, github.com, and GitHub Mobile. Copilot CLI is the command-line version of the assistant. GitHub also names JetBrains IDEs, Xcode, Eclipse, its Copilot app, and the coding agent. A user can check the model picker in the tool they already use as access becomes available. Source
Business and Enterprise administrators can manage the model through Copilot’s model policy. Under GitHub’s default enablement setting, a newly added model is enabled automatically unless the administrator turns off that global default or disables this specific model. If a team cannot see Sonnet 5.5, its administrator can check both the rollout status and these settings. Source
GitHub says use under usage-based billing follows the provider’s published list price. For the amount charged within a particular Copilot account, readers should check GitHub’s current models and pricing documentation rather than assume every plan treats the model identically. Source