Grok is now in Microsoft Copilot, but don’t expect snark in your spreadsheets

Developer September 14, 2026No Comments

Microsoft Copilot will soon support Grok models from xAI. Word, Excel, and PowerPoint users in the Microsoft Frontier Program can test Grok models now, with general support expected to roll out in the future.

Grok models are being added to Microsoft’s Online Services Subprocessor list. By offering different models as subprocessors, Microsoft can give customers access to those models without people having to switch away from the overall Copilot experience.

For example, Researcher Agent in Microsoft Copilot works with Claude AI models from Anthropic. Other Copilot experiences may use multiple AI models to complete tasks.

What is a subprocessor?

Subprocessors are third-party providers that help Microsoft deliver online services. Microsoft has an expansive list of subprocessors used for everything from powering data centers to completing tasks in Copilot.

Using Grok as a subprocessor helps Copilot tackle different tasks and provides redundancy that protects against outages or issues with other subprocessors. But users should not expect the witty or irreverent tone and style that Grok has become known for on X.

Subprocessors sit under Microsoft’s system prompts and enterprise guardrails, so the generated responses will still be professional. Essentially, you get the benefit of Grok’s multi-step logic and mathematical prowess but within Copilot.

Once an admin enables the integration, you can set Copilot in apps like Word, Excel, and PowerPoint to automatically pick the best model for a task, or manually pick between GPT, Claude, or Grok directly from a drop-down menu in the interface.