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

As the Office 365 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. Go to Office 365 ** admin center ** > Users > Active Users.

  2. Choose the user you want, and then click on Edit next to Mailbox permissions.

  3. In the search box under Send as, type the name of the user or users that you want to allow to send email from this mailbox.

  4. Once you've selected your users, click Save.

Allow another user to send email as this user

Read email in another user's mailbox

  1. Go to Office 365 ** admin center ** > Users > Active Users.

  2. Click or tap on the user you want, and then click or tap on mailbox permissions.

  3. In the search box under Read and manage email to this mailbox, type the name of the user or users that you want to allow to read email from this mailbox.

  4. Once you've selected your users, click Save.

Add users to read and manage this user's mailbox

Send email on behalf of another user

  1. Go to Office 365 ** admin center ** > Users > Active Users.

  2. Choose the user you want, and then click or tap on Edit next to Mailbox permissions.

  3. In the search box under Send on behalf, type the name of the user or users that you want to allow to send email on behalf of this mailbox.

  4. Once you've selected your users, click Save.

Allow another user to send on behalf of this user

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: