Give mailbox permissions to another user in Office 365 - Admin Help

Note

If you're not using the new Microsoft 365 admin center, you can turn it on by selecting the Try the new admin center toggle located at the top of the Home page.

As the admin, you may have company requirements to allow some users access to another user's mailbox. For example, you may want to enable an assistant to send or read email from their manager's mailbox, or one of your user's the ability to send email on behalf of another user. This topic shows you how to accomplish this.

If you're looking for information about creating and managing shared mailboxes, check out Create a shared mailbox.

Looking to set up mailbox permissions?

Mailbox permissions allow you to give read/write access to a mailbox to another user. The articles below might give you the help you need to set up and use this feature:

Setting up the permissions:

The first step to setting up permissions is deciding which actions you want to allow the other user to take in the given mailbox. You can allow a user to read emails from the mailbox, send emails on behalf of another user, and send emails as if they were sent from that mailbox. Refer to the following articles on how to set up each type of permissions:

Changing propagation:

Once you've set up the permissions, it can take up to 60 minutes for the changes to propagate through the system and be in effect.

How to use it once permissions are set up:

There are a few different ways you can access a mailbox once you've been given access. For help on this, refer to this article: Access another person's mailbox

Send email from another user's mailbox

  1. In the admin center, go to the Users > Active users page.

  2. Select the name of the user to open their properties pane.

  3. On the Mail tab, select Manage mailbox permissions.

  4. Next to Send as, select Edit.

  5. Select Add permissions, then choose the name of the person who you want this user to be able to send as.

  6. Select Save.

  1. In the admin center, go to the Users > Active users page.

  2. Select the user you want, expand Mail Settings, and then Select Edit next to Mailbox permissions.

  3. Next to Send as, select Edit.

  4. Select Add permissions, then choose the name of the person who you want this user to be able to send as.

  5. Select Save.

  1. In the admin center, go to the Users > Active users page.

  2. Select the user you want, expand Mail Settings, and then Select Edit next to Mailbox permissions.

  3. Next to Send as, select Edit.

  4. Select Add permissions, then choose the name of the person who you want this user to be able to send as.

  5. Select Save.

Read email in another user's mailbox

  1. In the admin center, go to the Users > Active users page.

  2. Select the name of the user to open their properties pane.

  3. On the Mail tab, select Manage mailbox permissions.

  4. Next to Read and manage, select Edit.

  5. Select Add permissions, then choose the name of the user or users that you want to allow to read email from this mailbox.

  6. Select Save.

  1. In the admin center, go to the Users > Active users page.

  2. Select the user you want, expand Mail Settings, and then select Edit next to Mailbox permissions.

  3. Next to Read and manage, select Edit.

  4. Select Add permissions, then choose the name of the user or users that you want to allow to read email from this mailbox.

  5. Select Save.

  1. In the admin center, go to the Users > Active users page.

  2. Select the user you want, expand Mail Settings, and then select Edit next to Mailbox permissions.

  3. Next to Read and manage, select Edit.

  4. Select Add permissions, then choose the name of the user or users that you want to allow to read email from this mailbox.

  5. Select Save.

Send email on behalf of another user

  1. In the admin center, go to the Users > Active users page.

  2. Select the name of the user to open their properties pane.

  3. On the Mail tab, select Manage mailbox permissions.

  4. Next to Send on behalf, select Edit.

  5. Select Add permissions, then choose the name of the user or users that you want to allow to send email on behalf of this mailbox.

  6. Select Save.

  1. In the admin center, go to the Users > Active users page.

  2. Select the user you want, expand Mail Settings, and then select Edit next to Mailbox permissions.

  3. Next to Send on behalf, select Edit.

  4. Select Add permissions, then choose the name of the user or users that you want to allow to send email on behalf of this mailbox.

  5. Select Save.

  1. In the admin center, go to the Users > Active users page.

  2. Select the user you want, expand Mail Settings, and then select Edit next to Mailbox permissions.

  3. Next to Send on behalf, select Edit.

  4. Select Add permissions, then choose the name of the user or users that you want to allow to send email on behalf of this mailbox.

  5. Select Save.

Send and read from Outlook and Outlook on the web for business

Want to know how to send email from another user's mailbox? Check out the following topics: