Change SharePoint Online Domain Name

When you first signed up for Microsoft 365, you created an onmicrosoft.com domain. Even if you later added a custom domain, the original onmicrosoft.com domain is used for all your SharePoint and OneDrive URLs.

If your organization has gone through a rebranding, merger, or acquisition and needs to change the domain in your SharePoint and OneDrive URLs, you can now do this using PowerShell. For example, if your organization name changed from Contoso (contoso.sharepoint.com) to Fabrikam (fabrikam.sharepoint.com), you can now change your SharePoint URLs from contoso.sharepoint.com to fabrikam.sharepoint.com.

The process has few limitations that are listed in the link provided as reference. Following are the steps to perform,

Step 1

• Connect to SharePoint as a global admin or SharePoint admin in Microsoft 365. To learn how, see Getting started with SharePoint Online Management Shell.

  Example:

  Connect-SPOService -Url "https://contoso-admin.sharepoint.com"

• Run the following command to specify the new domain name:

Start-SPOTenantRename -DomainName <DomainName> -ScheduledDateTime <YYYY-MM-DDTHH:MM:SS> [-WhatIf] [-Confirm]

Where "DomainName" is the part before "sharepoint.com" or "onmicrosoft.com" and "ScheduledDateTime" is at least 24 hours in the future, but not more than 30 days. The time you enter is based on the current date and time of the computer you're using.

Example:

Start-SPOTenantRename -DomainName "fabrikam" -ScheduledDateTime "2021-12-31T10:25:00"

You can get the status of the rename by running Get-SPOTenantRenameStatus. Make sure you open a new PowerShell window to sign in again. The date and time shown with this command is in UTC format. More info about Get-SPOTenantRenameStatus

During and after the rename, you can get the state of a site by running Get-SPOSiteRenameState. For more info about this cmdlet, see Get-SPOSiteRenameState.

To cancel a rename that has not started, you can run Stop-SPOTenantRename. More info about this cmdlet

Step 2

1. Review any firewall rules that might block access to the new domain.

2. Review organization browser settings to make sure the new domain is a trusted location. This includes reviewing any Group Policy settings that might control browser settings.

3. Review any third-party apps, custom apps, and scripts that access SharePoint. They might need to be modified to use the new domain.

Reference: https://docs.microsoft.com/en-us/sharepoint/change-your-sharepoint-domain-name