What changed in Copilot Wave 3 for Outlook
Copilot in Outlook has been updated as part of Microsoft's Wave 3 rollout (March 2026). There are three new features worth knowing about: automatic meeting scheduling from an email thread, email thread summaries, and smarter email drafting that can pull context from your calendar and recent conversations.
These require a Microsoft 365 Copilot licence — an add-on to standard M365 subscriptions. If you don't see a Copilot button in Outlook, check with your IT administrator. Many organisations have the licence but haven't enabled it for all users.
Feature 1: Summarise a long email thread before replying
This is the most immediately useful new feature for most people. Long email chains — especially ones you've been copied into — take significant time to read before you can reply intelligently. Copilot can now summarise the thread in one click.
Open an email thread in Outlook. Look for the Summarise button that appears above the message thread (or access it via the Copilot icon in the ribbon). Click it. Copilot reads the entire thread and returns a short summary covering what was discussed, what's been decided, and what's still open or needs action.
Read the summary, confirm it matches the thread, then reply. The time saving on a 20-message chain is significant — often 5 to 10 minutes per thread.
What to use this for
Long supplier or client email chains where multiple people have weighed in. Threads where you've been added mid-way through and need context quickly. Any chain with 10 or more messages before you need to reply.
Feature 2: Schedule a meeting from an email thread
When someone mentions catching up, scheduling a call, or meeting to discuss something in an email, Copilot can now handle the scheduling logistics without you switching to Calendar.
Open the email where a meeting was mentioned. Click the Copilot icon and ask: "Schedule a meeting with everyone on this thread." Copilot reads the thread, identifies the participants, checks everyone's calendar availability, suggests times, drafts an invite with a suggested agenda based on the email context, and presents it for your approval before sending anything.
You review the details, adjust if needed, and confirm. The invite is sent. You haven't opened Calendar once.
Feature 3: Draft a reply with context from your files and calendar
Copilot in Outlook can now draft email replies by pulling context from your recent calendar events, related emails, and connected files in SharePoint or OneDrive. This is useful when you need to reply to something that relates to work you've already done — a project update, a meeting outcome, a document you sent last week.
Open the email you want to reply to. Click the Copilot icon and select Draft with Copilot. In the instructions box, describe what you want to say and mention any relevant context. For example: "Reply agreeing to the proposal. Reference our call last Tuesday and the timeline we discussed."
Copilot looks at your recent calendar for a meeting with that person and uses that context in the draft. Review the result and edit anything that's off before sending.
Find the longest email thread in your inbox right now — one you've been putting off because it needs careful reading before you can reply. Click Copilot and use the Summarise feature. Read the summary, check it against the thread, then reply. Time how long that takes compared to reading the full thread yourself. For most people, this is the Outlook Copilot feature with the fastest payback.
One thing to check every time
Always read the Copilot-drafted reply before sending. Copilot works from context it can find — it can miss nuance, get names wrong, or misread the tone of a relationship. A 30-second review before hitting send protects you from sending something that's technically a reply but slightly off in a way that matters.
Copilot in Outlook works best as a first-draft and triage tool, not as a replacement for your judgment about how to handle a relationship or a sensitive situation.