How to set the postmaster address in Office 365



By default when Exchange Online in Office 365 is setup for your organization, the postmaster address, e.g. is set to

This means that when someone sends mail to your organization and gets an NDR back, the sender is:

If you want to change this, you can do so using PowerShell for Exchange Online.

The procedure for changing this is:

1. Connect to your Exchange online using PowerShell

2. Change addres using command:

Set-TransportConfig –ExternalPostmasterAddress


This works for All P and E plans – I have not tested it yet for K plan.

This postmaster address is a tenant/organization level setting which applies to all domains in your tenant. It is not available to set the postmaster address on a domain level.

About Author

Peter is an Exchange specialist with over 15+ years of experience with Exchange Server and certified Microsoft Certified Master (MCM) and Microsoft Certified Solutions Master (MCSM) on Exchange Server. He has been awarded the Microsoft MVP award, every year since 2007. He is active in the Microsoft community and User Group Leader for CoLabora (a danish UC & Cloud User Group). He works as an Cloud & Infrastructure Architect and Consulent, with primary focus on Exchange, Office 365, Azure and Skype for Business.


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