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Microsoft 365 Copilot

OpenAI's GPT 5.5 Thinking available in Copilot Chat

Released May 2026
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GPT 5.5 Thinking expands what Copilot Chat can do by enabling deeper reasoning and more complex problem solving.

Details:

What changed: Copilot Chat now includes GPT 5.5 Thinking, a model designed for multistep reasoning, structured analysis, and more thoughtful responses.

Why: Users need AI that can handle complex tasks such as planning, troubleshooting, and evaluating multiple options.

Try this:

  • Ask Copilot to break down a complex project into actionable steps.
  • Use GPT 5.5 Thinking to compare multiple strategies or solutions.
  • Request a detailed explanation of a technical or business process.

Why this matters:

Business impact: Supports more advanced decision making and planning.

Personal impact: Helps users think through complex tasks with greater clarity.

Applies to

  • Android
  • Windows
  • iOS
  • Mac
  • Web
View at Microsoft ↗ All Copilot updates

This is in the weekly digest for week 40 · What changed this week? →

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Text by Microsoft, from Microsoft's documentation. Features and dates may change. Terms and the timeline are added by 365Fanatic.