As announced on March 18, 2026, GPT-5.3-Codex is now the base model for all Copilot Business and Copilot Enterprise organizations, replacing GPT-4.1. The base model is used when your organization hasn’t yet approved other models through its internal review process.
GPT-5.3-Codex is also our first long-term support (LTS) model, in partnership with OpenAI. LTS models are guaranteed to be available for a full 12 months from the model’s launch date, giving enterprises the stability they need for internal security and safety reviews. GPT-5.3-Codex launched on February 5, 2026 and will remain available through February 4, 2027 for Copilot Business and Copilot Enterprise users.
GitHub Copilot data has shown that GPT-5.3-Codex has a significantly high code survival rate among enterprise customers.
Premium request multipliers
GPT-5.3-Codex carries a 1x premium request unit multiplier. GPT-4.1 will remain force-enabled at a 0x multiplier for the time being, though it will deprecate alongside the launch of usage-based billing on June 1, 2026.
