Setting Up Auto-Replies for Aliases in Microsoft 365 Shared Mailboxes Print

Overview

In Microsoft 365 Exchange Online, you can create a single Shared Mailbox that handles multiple departmental addresses (for example, sales@, support@, billing@, and info@).

Using Mail Flow Rules, you can configure Microsoft 365 to send automatic replies unique to each alias, all while managing everything from one shared inbox and without purchasing additional licenses.

How It Works

• A Shared Mailbox allows multiple people to access and manage the same inbox.
• You can assign several aliases (alternate addresses) to that shared mailbox, such as:
  • sales@domain.com
  • support@domain.com
  • billing@domain.com

All incoming messages to those aliases deliver into the same shared mailbox. This keeps things simple: one inbox, no extra license cost, and the flexibility of multiple "faces" for your company.

Prerequisites

• Microsoft 365 Administrator access
• Access to the Microsoft 365 Admin Center and Exchange Admin Center (EAC)

Step 1 - Create the Shared Mailbox

1. Go to the Microsoft 365 Admin Center
2. Navigate to Teams & Groups > Shared Mailboxes
3. Create a new shared mailbox (for example, info@domain.com)
4. Add any users who should have access to the mailbox

Step 2 - Add Aliases

1. Open the mailbox's properties
2. Add additional email addresses such as sales@domain.com and support@domain.com

All messages sent to these aliases will deliver to the shared mailbox.

Step 3 - Create Mail Flow Rules

1. Open the Exchange Admin Center (EAC)
2. Navigate to Mail Flow > Rules
3. Click Add (+) and choose Create a new rule
4. Give the rule a descriptive name (for example, "Auto-Reply for sales@domain.com")
5. Under Apply this rule if..., choose The recipient is and select the alias (for example, sales@domain.com)
6. Under Do the following..., select Reply with message and enter your desired auto-reply text
7. Click Save

Step 4 - Repeat for Each Alias

Create a separate Mail Flow Rule for each alias (support@domain.com, billing@domain.com, etc.), each with its own custom auto-reply message.

Step 5 - Test the Configuration

1. Send a test email to each alias
2. Verify the correct auto-reply message is triggered for each address

Notes

• No paid license is required for a Shared Mailbox
• Auto-replies will always come from the shared mailbox's primary address, not the alias, but the sender will still receive the correct message
• This method provides centralized message management and retention
• Team members can access the shared mailbox from Outlook or Outlook on the Web