Copilot Chat

Copilot Chat is Microsoft's AI assistant inside Microsoft 365. You can use it for much of what you would use ChatGPT for: writing, analysing, summarising, researching and working through tasks. What makes it particularly interesting for Microsoft 365 users is how closely it connects to the tools and information you already work in.

Copilot Chat works both with and without the paid Copilot licence, but there is a big difference in what it can reach. Without Premium you have to hand Copilot most of the material yourself, for example by uploading files or pointing to them. With the M365 Copilot add-on licence (Premium), Copilot can also pull relevant information from across Microsoft 365, including email, meetings, Teams and files you have access to.

For the rest of this article we call the paid version Copilot Premium.

What you can do

Copilot Chat suits tasks where you would otherwise spend time searching, reading, comparing or producing a first draft.

You can ask it to summarise a long document, compare two proposals, turn notes into a tidy report, or research a topic using sources on the web.

With Copilot Premium it becomes especially useful when the information is scattered. You can ask something like: "I'm meeting Company B this afternoon. What have we discussed with them before, which issues are still open, and what should I follow up on?" With Premium, Copilot can go looking for relevant information in Microsoft 365 on its own, as long as you already have access to it.

You can also steer Copilot more precisely by typing "/" and pointing to specific sources. With Premium that can be a file, a person, a meeting or an email.

Copilot Chat also has agents. An agent is a tailored version of Copilot built for a particular task, or given specific knowledge sources and tools (for example an agent that knows the staff handbook, acts as an assistant on one project, or always produces status reports the same way). You do not need to know how to program to build a simple one.

AI models

OpenAI models are still central to Copilot, but Microsoft now uses models from other providers too. In 2026, Claude from Anthropic became available as a model option in Copilot Chat.

Copilot Premium also gives you priority model access, along with advanced reasoning and model selection. Which options you actually see can vary with your organisation's setup and which features Microsoft has rolled out to your user.

Limitations of the free version vs Copilot Premium

Free version (Copilot Chat and M365 Copilot Basic, included in qualifying Microsoft 365 licences).

• Copilot cannot freely search email, Teams conversations, meetings and other work data across Microsoft 365.
• You can use some agents, but access is limited.
• You get standard access to the AI models. Microsoft notes that capacity can be more limited when traffic is high. During "rush hour" Premium users are prioritised, so response times can be longer.

Premium

• Full access to Work-IQ, so Copilot can find relevant information in meetings, email, chats and files you already have access to.
• Priority access, which Microsoft describes as faster and more reliable.
• Broader agent access, including advanced Microsoft agents such as Researcher and Analyst. Researcher is built for larger research tasks and can combine information from the web with files, email, meetings and conversations you have access to.

The line between Copilot Chat / Basic and Premium is not entirely black and white. Microsoft has gradually moved more Copilot features into the ordinary Microsoft 365 apps. Outlook is a good example: even without Premium, Copilot Chat can use some information from your inbox, calendar and meetings when you use Copilot directly in Outlook.