The Power Of Plus: Microsoft Gets On Board

plus address

One of the most powerful things about Gmail is that you can add a “+tag” to your email address, turning your single email address into an infinite amount of addresses. These modified plus addresses can then be used to filter email with great precision.

Microsoft finally is getting on board with this, setting the Plus addressing as a default as of April 22, 2022. It can still be overridden by system administrators, but hopefully most people will take the default.

Simply put, you will be able to use the “+tag” on your Outlook email address and take advantage of the built-in filtering to quickly sort your mail.

Using the +Tag

For instance: would be the base address. This could be expanded to:


All of these email address will end up in the regular inbox, but each with have a

different To address.

Why Use Plus Addresses?

The power of the plus addresses lies in where you give it out. If you choose to use a

“+newsletter” address for every email list you sign up for, you will be able to

immediately distinguish all of your mailing list emails.

Using Plus To Find Who Is Selling Your Email

You can also use it to find out who is selling your email address.

For instance, I gave my address on an order to a garden tool supply company using a

“+garden” modifier. All my email from them comes to that address. What I noticed

about three months later was that the “+garden” address was being used from

businesses who sold plants, and then later by businesses who sold fundraising, and

then later by businesses who sold magazines.

With that level of email address sale going on, I was able to create a filter for that

address and send everything right to trash. And I made sure never to buy anything

from that original company again.

How I Use This At Work

At work, I have two systems: test and production. Each system generates emails for the following types of tasks:

  • File imports
  • Vendor file processing
  • Operational Data Store processing
  • Data Warehouse processing
  • Internal extract
  • Vendor extracts

The structure of the emails, particularly for the imports, file processing and extracts, are not consistent. It depends on which company is doing the imports, processing and extracts and is not something my team has control over.

We get upwards of 400 emails a day from these systems.

Setting up a “+tag” address will make it easy to filter these. We start with “datagroup+test” and “datagroup+production” as the base and go from there, expanding it to “datagroup+testimports” and “datagroup+productionimports” for example.

This will give us a much more solid way to filter than to pick out unique phrases from the bodies of the email in question. Instead of moving an email based on “from ‘testserver’ sent to ‘DataGroup’ and with ‘file import’ in the subject line and with ‘error’ or ‘fail’ or ‘abort’ in the body” this would become “sent to ‘DataGroup+testfail’”


Using the + address is a powerful way to categorize your email as it comes into the inbox. Take advantage of it – your email will never be the same again!