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Enabling plus addressing/aliasing in Microsoft 365

Paul Barton

Product: Exchange Online

Since this article was first written in December 2021 Microsoft has enabled plus addressing for all tenants. Therefore the original content from this article has been removed and replaced with instructions on disabling it.

This has been retested on Windows 11 running PowerShell 5.1

If you need to install and import the ExchangeOnlineManagement module:

Set-ExecutionPolicy Unrestricted
Install-Module -Name ExchangeOnlineManagement -Force
Import-Module -Name ExchangeOnlineManagement

Using an elevated Powershell / Powershell 7 prompt use:

Connect-ExchangeOnline

To disable plus addressing organisation-wide:

Set-OrganizationConfig -DisablePlusAddressInRecipients $true

Then disconnect from Exchange Online and set the execution policy back to restricted:

Disconnect-ExchangeOnline
Set-ExecutionPolicy Restricted

What is Plus Addressing

Plus addressing allows end-users to create additional email addresses on-demand, for a specific purpose or service.

For example david@365labs.cloud might want to use david+facebook@365labs.cloud, when signing up to Facebook.

See this content in the original post