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Microsoft 365 Copilot: The Complete Guide

A practical, evergreen guide to Microsoft 365 Copilot: what it actually does across Word, Excel, PowerPoint, Teams and Teams Phone, licensing basics, and how it's evolving into an agentic system.

Microsoft 365 Copilot started as an AI writing assistant bolted onto Word and Outlook. It’s grown into something closer to an agentic layer across the entire Microsoft 365 stack, capable of executing tasks end to end rather than just drafting text. This page is the hub for everything I’ve written about it: what it does today, where it’s heading, and links to the deeper posts I keep updated as things change.

For the month-by-month changelog, see my What’s New in Microsoft 365 Copilot series.

What Copilot actually does

At its core, Copilot works in two modes:

Chat — you ask a question, Copilot answers using Microsoft 365 data it has access to (your emails, files, meetings, chats), grounded through what Microsoft calls Work IQ.

Agentic work (Copilot Cowork) — you define a task, and Copilot plans, executes, and delivers a finished result, not a draft you still need to act on. This is the more recent and more significant shift: Cowork can build a deck, research a competitor, or draft a document end to end, pulling in plugins for connected business systems along the way.

Which mode you need depends on the task. Quick questions and lookups fit Chat. Anything that used to be “I’ll do this properly later” fits Cowork.

Copilot across the Microsoft 365 apps

  • Word — drafting, rewriting, and now agentic editing that can act directly on document comments and insert images inline.
  • Excel — formula help, data analysis, and reusable custom skills for repeatable analysis tasks.
  • PowerPoint — deck generation grounded in your own SharePoint/OneDrive content, with brand-kit support so output starts on-brand.
  • Teams — meeting recaps, notes, and increasingly, agents like Facilitator and Interpreter working live during meetings.
  • Teams Phone — Copilot can now summarize live calls in real time and, more recently, take call delegation, answering calls on your behalf and scheduling follow-ups. See my Teams Phone guide for more on this.

Licensing

Microsoft 365 Copilot is a paid add-on license on top of an eligible Microsoft 365 plan, it isn’t bundled in by default. Licensing details and eligible base plans shift often enough that I won’t pin an exact price here, check the Microsoft 365 Copilot pricing page for the current state. Some newer capabilities, like Copilot Cowork, use usage-based billing (Copilot Credits) on top of the base license, so budget for both if you’re rolling this out at scale.

Copilot is becoming multi-model

A recent and important shift: Copilot is no longer a single-model product. Anthropic’s Claude models are now available alongside OpenAI’s models in several Copilot surfaces, including Copilot Cowork and Copilot in Word, with the system able to route a task to whichever model fits it best (for example, using a Claude model for visual/PowerPoint work and a GPT model for research with citations). If model choice matters to your organization, this is worth checking per-app rather than assuming it’s the same everywhere.

Governance and admin controls

As Copilot’s footprint grows, so does the admin tooling around it: a Cost Management Dashboard for usage-based billing, organization-published prompts to guide good usage, and Purview DLP controls that extend to Copilot Cowork specifically. If you’re rolling Copilot out beyond a pilot group, set up cost controls before adoption, not after, usage-based billing without limits is how surprise invoices happen.

Frequently asked questions

Do I need a Microsoft 365 Copilot license for every Copilot feature I see mentioned? Mostly yes, but not always. Some capabilities (like certain Teams meeting features) are tied to a Teams Premium or other add-on license rather than Copilot specifically. Check the specific feature’s licensing requirement rather than assuming Copilot covers everything.

Is Copilot Cowork the same as Copilot Chat? No. Chat answers questions using your data. Cowork executes multi-step tasks and hands back finished work. They’re complementary, not the same feature under a different name.

Can I choose which AI model Copilot uses? In a growing number of places, yes, model choice is rolling out across Cowork, Word, and other surfaces, though availability depends on your tenant, region, and admin configuration.

Does Copilot train on our company data? No. Microsoft 365 Copilot is designed so your organizational data isn’t used to train the underlying foundation models. Always verify current data handling commitments in Microsoft’s official Copilot documentation, since this is exactly the kind of detail worth confirming from the primary source rather than a blog post.

Questions about rolling out Copilot in your organization? Drop a comment below or find me on LinkedIn.