GitHub announces long-term support for GPT-5.3-Codex in Copilot

GitHub has established long term support models for Copilot Business and Copilot Enterprise. The models aim to give enterprises stability for internal security and safety reviews. Designated long term support models will be available for a full 12 months from the launch date. GPT-5.3-Codex is the first long term support model through a partnership with OpenAI. The model launched on February 5, 2026 and will remain available through February 4, 2027 for Copilot Business and Copilot Enterprise users. GitHub Copilot data shows that GPT-5.3-Codex has a significantly high code survival rate among enterprise customers. The model will also serve as the newest base model for Copilot, replacing GPT-4.1. GitHub will automatically enable GPT-5.3-Codex for all Copilot Business and Copilot Enterprise organizations within 60 days of the announcement. The model carries a 1x premium request unit multiplier. GPT-4.1 will remain force enabled at a 0x multiplier for the time being. These changes apply to Copilot Business and Copilot Enterprise plans only. They do not apply to Copilot Pro, Copilot Pro+ or Copilot Free. On individual plans, model deprecation will follow the standard timeline.