Long-Term Support Program

GitHub has introduced a new long-term support (LTS) commitment for GitHub Copilot Business and Enterprise users, addressing enterprise needs for stability during internal security and safety reviews. Models designated as LTS will remain available and supported for a full 12 months from their launch date, providing predictable deprecation timelines for organizations with complex approval processes.

GPT-5.3-Codex as First LTS Model

GPT-5.3-Codex is the inaugural LTS model, developed in partnership with OpenAI. The model launched on February 5, 2026, and will be available through February 4, 2027 for both Copilot Business and Enterprise subscribers. GitHub's internal metrics show that GPT-5.3-Codex has achieved significantly high code survival rates among enterprise customers.

Model Transition Timeline

GPT-5.3-Codex will automatically replace GPT-4.1 as the default base model for all Copilot Business and Enterprise organizations within 60 days of this announcement (by May 17, 2026). The new model carries a 1x premium request unit multiplier, while GPT-4.1 will temporarily remain force-enabled at a 0x multiplier to allow for transition time. Organizations needing extended transition periods should contact their account teams.

Scope and Applicability

These changes apply exclusively to Copilot Business and Copilot Enterprise plans. Copilot Pro, Pro+, and Free tiers will follow standard model deprecation timelines. For complete details on supported models and organizational policies, refer to GitHub's documentation on supported models and model management.