A feature that has been missing for a long time in Microsoft Exchange, and something a lot of Exchange Admins may not have even known existed, is the concept of “Plus Addressing”. Plus addressing essentially allows an additional ‘tag’ to be added to a sent email, this ‘tag’ or ‘plus address’ helps provide context around the incoming email for the recipient. It also means that users themselves can create dynamic addresses for particular projects or customers to help sort incoming mails without any support tickets or admin intervention.

Plus Addressing isnt a new concept, in fact, it’s been around quite a while in other mail systems and even in Outlook.com accounts. Microsoft announced in 2019 that this feature was in the works and it is now live for everyone to try!

How does Plus Addressing work?

A typical email address in our exchange system looks like this:

user@domain.com

When we add plus addressing into the mix, we get an email address like the this:

User+Customername@domain.com

Now when an email is sent to the user, it will still arrive in their mailbox, but will be tagged as such. In the below example we can see a plus address in action:

When the mail comes in with a plus address it can easily be sorted into the correct location or folder in the recipient mailbox without any admin intervention!

Enabling Plus Addressing

Plus addressing can be enabled very easily in the Exchange Online Organization Config by running the below command in the Exchange Online PowerShell Module:

Set-OrganizationConfig -AllowPlusAddressInRecipients:$true 

Once this is set, it’s just a matter of letting users know about the functionality!

There are a lot of use cases for plus addressing I’ve come across in the past, things that required a ton of Shared Mailboxes or Distribution Groups come to mind. Mailboxes which take in customer requests are another great example.

A plus address can also be added long term by adding the address using PowerShell for when it needs to be assigned and visible in the organization.

Plus Addressing is a cool tool which brings a lot to those specific use cases that cause messy workarounds to be put in place. Make sure when implementing to check any third party spam filter that you may have supports them too!