Microsoft defaults GPT-5.6 in Copilot

Microsoft and GitHub have already made OpenAI’s GPT-5.6 family a central part of Copilot, according to company posts published on July 9. GitHub said GPT-5.6 Sol, Terra and Luna were rolling out in GitHub Copilot, while Microsoft said the same model family was available in Microsoft 365 Copilot and had been made the “preferred model” for that product. (github.blog) The new defaulting matters because Microsoft has been presenting two strategies at once. Microsoft’s product teams are expanding GPT-5.6 across Copilot surfaces, while other parts of the company are also pushing in-house MAI models into products such as Excel and Outlook to reduce outside model costs, according to a July 7 BigGo Finance report that cited comments from AI chief Mustafa Suleyman. (github.blog) A second pressure point is money. BigGo Finance reported on August 5 that Microsoft’s latest filing showed OpenAI contributed $24.1 billion in revenue in the fiscal year ended June 2026, about 70% of Microsoft’s total AI sales. (github.blog) Microsoft has also disclosed that OpenAI-related gains affected earnings and that revenue-share payments from OpenAI continue through 2030 under the revised partnership terms announced in April. ### Where did the “default” idea actually come from? GitHub’s own July 9 changelog stops short of saying GPT-5.6 Sol is the universal default across Copilot. The post says GPT-5.6 Terra is “the balanced default,” describes Sol as the highest-reasoning option for harder coding tasks, and says enterprise administrators must enable GPT-5.6 access because the policy is off by default. (techcommunity.microsoft.com) Microsoft used firmer language in its July 9 Microsoft 365 Copilot announcement. The company said OpenAI and Microsoft had optimized GPT-5.6 for work across Word, Excel, PowerPoint, Chat and Cowork and had made it the “preferred model” for Microsoft 365 Copilot. (finance.biggo.com) That leaves a narrower, more supportable version of the story than some secondary reports suggested: Microsoft is not publicly saying one single GPT-5.6 variant now overrides every other model everywhere, but it is steering Copilot users toward GPT-5.6 across major products. (github.blog) ### How broad is GPT-5.6 inside Microsoft’s stack? Azure’s own model catalog shows GPT-5.6 Sol, Terra and Luna are available as Azure OpenAI models in Microsoft Foundry. GitHub said the models can be selected in Visual Studio Code, Visual Studio, Copilot CLI, github.com, mobile apps and other development environments. (techcommunity.microsoft.com) Microsoft 365 Copilot release notes show the product continues to roll out features gradually inside tenants under a “safe deployment model.” That means the practical effect of a preferred model can vary by product, tenant settings and admin policy, even when the company’s direction is clear. (github.blog) ### Why does this matter for customers buying Copilot? GitHub said GPT-5.6 models in Copilot are billed at provider list pricing under usage-based billing. That makes model choice more than a product-design issue: defaults can shape spend, workflow design and how much effort an enterprise must invest to keep alternatives available. (learn.microsoft.com) September 1, 2026, is the next concrete date to watch. GitHub said it will deprecate several models across Copilot experiences on that date and told enterprise customers to update workflows and integrations to supported alternatives, with admins controlling access through model policies. (learn.microsoft.com) (github.blog 1) (github.blog 2)