Copilot Notebooks

Canonical version: Copilot Notebooks.

Copilot Notebooks (officially Microsoft 365 Copilot Notebooks) is Microsoft's AI project workspace. You gather everything related to a piece of work in one notebook: Copilot chats, Word documents, PowerPoint decks, Excel sheets, PDFs, Loop files, OneNote pages and links. Copilot then answers your questions using those references as ground truth. Microsoft calls it "your AI-powered project brain".

It launched in July 2025. It's available in OneNote (a Copilot Notebooks section sits at the top of the notebook list) and in the Microsoft 365 Copilot app.

Where the idea comes from

Half of it is the idea behind Claude Projects in Claude, ChatGPT Projects in ChatGPT and Gems in Gemini: a persistent workspace with its own files and instructions, so you don't re-explain the context in every new chat. Each notebook gets its own Copilot Instructions (tone, format, what to focus on).

The other half is NotebookLM. Source-grounded answers, Audio Overviews and mind maps all come from there, almost feature for feature, so on this front Microsoft is catching up with Google (which renamed NotebookLM to Gemini Notebook in July 2026).

Microsoft's advantage is that your files are already there. If your organization runs on Microsoft 365, the documents live in SharePoint and OneDrive, and a notebook points at them directly instead of holding uploaded copies. Sharing works the same way: share a notebook with a Microsoft 365 Group and access follows group membership.

Curated sources plus per-workspace instructions is Context Engineering packaged for people who will never write a prompt file, with Retrieval-Augmented Generation (RAG) doing the grounding. None of that is new. What I think decides adoption is location: for teams whose work already sits in Microsoft 365, this is the AI workspace that has their files without any setup.

What you can do with it

• Ask questions grounded in the notebook's references
• Generate summaries, action items and drafts
• Set Copilot Instructions per notebook
• Generate an Audio Overview, a podcast-style conversation summarizing the references. English only at launch; voice, tone and length became customizable later
• Generate Mind Maps from the references
• Export results as structured Word documents or PowerPoint decks
• Add whole OneNote notebooks and SharePoint sites or folders as references (added in 2026)
• Share a notebook with a Microsoft 365 Group

Limits and licensing

At launch you could add more than 20 references, but Copilot only used the first 20 for grounding. Supported formats: .docx, .pptx, .xlsx, .pdf, .loop and OneNote pages. No support for Markdown unfortunately (but well for .txt files, which is disappointing).

It first shipped for work accounts with a Microsoft 365 Copilot license plus SharePoint or OneDrive. Microsoft later opened it to Copilot Chat licenses and to Microsoft 365 Personal, Family and Premium subscribers.

Notebooks, Pages and agents

Rob Quickenden describes notebooks as "persistent, AI-grounded project workspaces". In his split, Copilot Pages (built on Loop) hold the deliverables, and the notebook is the iterative canvas where the work takes shape. He calls agents static, and notebooks "a living, breathing collaboration space".

References

• Introducing Copilot Notebooks: a whole new way to work with AI in OneNote (Gokul Subramaniam, Microsoft, 1 July 2025, updated 16 September 2025): https://techcommunity.microsoft.com/blog/microsoft_365blog/introducing-copilot-notebooks-a-whole-new-way-to-work-with-ai-in-onenote/4428626
• Copilot Notebooks: enhancements to support creation, collaboration and learning (Microsoft, 2026): https://techcommunity.microsoft.com/blog/microsoft365copilotblog/copilot-notebooks-enhancements-to-support-creation-collaboration-and-learning/4505360
• What are Microsoft 365 Copilot Notebooks in OneNote (Microsoft Support): https://support.microsoft.com/en-us/microsoft-365-copilot/what-are-microsoft-365-copilot-notebooks-in-onenote
• What are Copilot Notebooks? (Rob Quickenden, third-party blog, 30 March 2026): https://robquickenden.blog/2026/03/what-are-copilot-notebooks/

Related

• NotebookLM
• Microsoft
• Claude
• ChatGPT
• Gemini
• Context Engineering
• Retrieval-Augmented Generation (RAG)
• Mind Maps

About Sébastien

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