How to List All Users with a Configured SMTP Forwarding Email

How to find users with an SMTP forwarding email

Have you ever had to find all the users who have configured SMTP forwarding emails only to realize that using the Microsoft admin center to do this is really tedious? To create the list using the admin center, you must perform the whole process manually which is time consuming and prone to errors.

Using the Microsoft Admin Center to find users with SMTP forwarding email addresses

If you’re in the Microsoft 365 Admin Center and look at your list of active users in the admin center, you’ll notice that the property you need Is not available. So, right off the bat, there is no way to see who has a configured SMTP forwarding address. To find this information you will need to:

  1. Click on each user listed in the active user list.
  2. On each user’s screen, go to the mail tab to see if the email forwarding has been applied.
  3. If it is applied, you need to click on the “manage email forwarding” link to see where the emails are being forwarded.
Look up SMTP forwarding email addresses in the Microsoft 365 Admin Center

If you’re looking to find only mailboxes which are set with external SMTP forwarding, then you’ll need pay even closer attention.

Note that there are other settings in Exchange Online that forward incoming email messages. You can read about them our previous article “Best way to find and remove mail forwarding rules in Exchange Online”.

If you are part of an organization with a lot of users, this process will take a lot of time and patience.

Your other option is to write a PowerShell script. If you are not comfortable writing code, you will have to search for a script online that will do the job.

Using PowerShell to find users with SMTP forwarding

You’ll first need to connect to Exchange Online with this cmdlet: Connect-ExchangeOnline.

The SMTP forwarding address is a mailbox property so the Get-Mailbox cmdlet is used to get it for a specific mailbox: Get-Mailbox -Identity email@company.com | select UserPrincipalName,ForwardingSmtpAddress .

To get the list of mailboxes with a value set for the ForwardingSmtpAddress property, you can try using a non-null filter as a parameter on the cmdlet: Get-Mailbox -Filter { ForwardingSmtpAddress -ne $null} | select UserPrincipalName,ForwardingSmtpAddress

If you want your report to include only users with external STMP forwarding, you’ll need to analyze and arrange the results, or improve your script to do it for you.

Using sapio365 to find and list users with configured SMTP forwarding emails

If you want to avoid writing code, a PowerShell alternative like sapio365 can offer another option for completing this task with less effort and in less time.

  1. In sapio365, load all your users from the main page by clicking on “users”. You will see all your users and the properties in the default view.
Load mailbox properties in sapio365
  1. Go to the column map in the top menu to see all the properties available.
  2. Search for SMTP related properties.
  3. Select the ones you need and add them to the grid. From that list of users, it is now easy to see those with forwarding emails.
  4. Isolate and filter by going to the sort/filter tab on the top menu.
Filter out empty SMTP forwarding values in sapio365
  1. Remove the rows with empty values to isolate the users. You will also be able to see which users have chosen to keep a copy of the forwarded emails.
  2. Save the view.
Regular expression filter in sapio365

You can also decide if you need to change any of the SMTP forwarding addresses or change any of the settings. For example, you may decide that that all users should keep a copy of the forwarded emails.

Once you apply your changes, the changes will appear in green so you can review them before saving, preventing any unexpected errors.

Update SMTP forwarding property to keep a copy of emails

A software tool like sapio365 provides an option for Microsoft 365 Office IT admins who can’t write code and for those who don’t want to search for a PowerShell script. Not only will you be able to find users with an SMTP forwarding email, but you can use it to perform your other email-related tasks, like finding missing Exchange Online emails or examining inbox rules. Discover how using sapio365 to handle typical Microsoft 365 administration can save you hours of time every single day.


Eric Houvenaghel

Eric’s passion is solving problems. It’s why he founded his company Ytria – so he could solve problems people had that they didn't even realize they had. With over 2 decades of experience as a software developer, Eric honed his expertise by crafting innovative solutions tailored to the needs of IT teams in both Microsoft 365 and Notes/Domino environments.