OpenAI Makes GPT-5.6 the Preferred Model in Microsoft 365 Copilot

On July 9, 2026, OpenAI announced that its new-generation model GPT-5.6 will serve as the "preferred model" in Microsoft 365 Copilot. It becomes available across Word, Excel, PowerPoint, Copilot Chat and Copilot Cowork, with Microsoft offering it both through native integration and directly via the OpenAI API. It is also rolling out to GitHub Copilot at the same time. (announcement, Microsoft's post)