Use Copilot in Shared and Delegate Mailboxes: Smarter Email Management for Teams

18 February 2026

Shared and delegate mailboxes are a big part of how most teams work day to day. Whether it’s support requests, finance queries, sales enquiries, or covering an executive inbox, these mailboxes can get busy very quickly. Keeping on top of them often means trawling through long threads just to work out what’s going on.

Microsoft 365 Copilot now supports shared and delegate mailboxes, which means you can use Copilot to help read, summarise, and take action on emails in those inboxes. It’s a simple change, but it makes a noticeable difference when you’re dealing with high‑volume or shared email.

Note: Any email addresses used below are illustrative examples only.

Why this is actually useful

When more than one person is managing a mailbox, things can easily slip:

• Long email chains take time to catch up on
• Context gets lost between handovers
• Replies get duplicated or slightly inconsistent
• Time is spent reading rather than responding

Copilot helps by quickly summarising what’s happened, pulling out relevant emails, and helping you draft replies using the existing context. That means less time in the inbox and fewer missed details.

What Copilot can do in shared and delegate mailboxes

Using the Microsoft 365 Copilot app, you can read and take action on emails in both shared and delegate mailboxes. This includes:

• Summarising recent emails
• Finding emails related to a specific topic
• Helping draft responses based on existing conversations
• Quickly seeing what’s changed since you last checked the mailbox

This works for both mailbox owners and delegates, as long as the right permissions are in place.

A quick note on permissions

Copilot won’t work on a delegate mailbox if you only have shared folder permissions.

To read or take action on a delegate mailbox using Copilot, you need full delegate access. This is worth double‑checking, especially for executive assistants, finance teams, or anyone covering someone else’s inbox.

Before you start

To use Copilot with shared or delegate mailboxes:

• You need a Microsoft 365 Copilot licence
• You need to access the mailbox via the Microsoft 365 Copilot app (web or desktop)
• For delegate mailboxes, you need full delegate permissions

Without these, Copilot won’t be able to interact with the mailbox content.

Using Copilot with a shared mailbox

To get started:

1. Open Microsoft 365 Copilot (web or desktop)
2. Sign in with your work or school account
3. Enter your prompt in the Chat window and select Send

Example prompts for shared mailboxes

For example:

• “Summarise recent emails in the support@maple.com mailbox”
• “List all emails about invoices from the finance@maple.com mailbox”
• “Summarise unread emails in the sales@maple.com mailbox”

Tip: Make sure you include the word “mailbox” in your prompt so Copilot knows you’re referring to a shared mailbox and not your personal inbox.

Using Copilot with a delegate mailbox

The process is the same:

1. Open Microsoft 365 Copilot
2. Sign in with your work or school account
3. Enter your prompt and select Send

Example prompts for delegate mailboxes

You might ask:

• “Summarise recent emails in the Managing Director’s mailbox”
• “List recent emails about contracts in the Finance Director’s mailbox”
• “Summarise emails from last week in the Operations mailbox”

Again, including “mailbox” in the prompt is important so Copilot applies the action correctly.

Using Context IQ (CIQ)

To make things quicker, you can use Context IQ. Type a forward slash / and start typing the name or mailbox reference you want. Copilot will suggest relevant people or mailboxes based on what you type, which helps reduce errors and saves time.

Where this really helps day to day

This update is particularly useful for:

• Support teams managing shared helpdesk inboxes
• Finance teams dealing with invoices and payment queries
• Sales teams handling shared enquiries
• Executives and assistants working with delegate access
• Regulated organisations where context and consistency matter

Instead of spending time piecing together email history, Copilot helps you get up to speed quickly and respond with confidence.

Copilot support for shared and delegate mailboxes won’t fix poor permissions or messy inboxes, but when those basics are in place, it’s a genuinely helpful way to reduce email admin and keep things moving. For teams already using shared mailboxes heavily, this is one of the more practical Copilot features available right now.