M365 Copilot vs Copilot Studio vs Microsoft Foundry: Which Layer of Microsoft AI Do You Need?

If you only learn one mental model for Microsoft AI, make it this one. M365 Copilot is where you use AI at work, Copilot Studio is where you build AI agents with low code, and Microsoft Foundry is where you engineer AI at enterprise scale. Most confusion about Microsoft's AI stack disappears once you know which layer a conversation is actually about.

The comparison on one page:

Want the hi-res version? It's free in the Powercademy Success Kit, along with hundreds of other Microsoft AI and Power Platform resources.

What's the difference at a glance?

When should you use M365 Copilot?

M365 Copilot is the starting place for AI at work - Chat, Agents, Pages, Notebooks, and your Microsoft 365 apps in one hub, grounded in your Microsoft Graph data. Use it when you want chat-based help that understands your files, emails, and meetings; when you need simple apps (dashboards, forms, lists) via App Builder; or when you want to automate tasks across Outlook, Teams, and SharePoint with Workflows.

Everyday wins: summarising long Outlook threads and drafting context-aware replies, "describe it to automate it" workflows like daily digests and file routing, and Excel analysis with suggested formulas and charts. It's deeply integrated with Microsoft Graph, builds apps and automations with no code, and doesn't train its foundation models on your business data.

The limits: it needs a Copilot licence and admin setup, admins may have locked features down, and App Builder and Workflows are still rolling out.

When should you use Copilot Studio?

Copilot Studio is the low-code studio for building, managing, and publishing AI agents - extend Microsoft 365 Copilot with organisation-specific skills, or create standalone agents and publish them to the web, Teams, or externally for customers. Connect to business data via connectors and plugins, orchestrate agent flows that call actions and tools, and extend your model-driven apps and Dynamics agents.

It has the friendliest interface for building and extending Copilots, making them fast to create - and it's the natural path for Power Platform professionals. The trade-offs: complex actions may need Azure services, production use needs real ALM for lifecycle, testing, and connections, and you'll want Power Platform skills to be productive. For where the platform is heading, see Copilot Studio classic vs the new harness.

When should you use Microsoft Foundry?

Microsoft Foundry is Azure's unified platform to design, build, evaluate, and operate AI apps and agents at scale - model catalogue (OpenAI and others), safety tooling, agent runtime, and enterprise controls for identity, networking, and monitoring.

Reach for it when you need full control over models, networking, data, and deployment; when you're integrating multiple tools and services with enterprise security and observability; or when AI goes deep inside existing enterprise apps. Build custom copilots that call tools and enforce content safety, evaluate and swap models from a central catalogue, and power domain-specific agents with custom models and APIs.

The costs: Azure skills are required, spend can scale quickly with large models, and there's more setup and operations overhead than the other two layers.

How do the three layers fit together?

Think of it as a pyramid of control versus convenience:

• Everyone in the organisation uses AI in M365 Copilot

• Makers and Power Platform teams build agents in Copilot Studio - often surfacing them back into M365 Copilot

• Engineering teams operate custom AI in Microsoft Foundry - often powering what Studio agents call behind the scenes

They're not competitors; they're the same stack at three altitudes. The question is never "which is best" - it's which altitude your problem lives at.

FAQ

The hi-res, printable version of this comparison is in the Powercademy Success Kit - free, along with hundreds of other cheat sheets, roadmaps, and guides for Microsoft professionals.