For a personal Microsoft account, change the phone number in Manage how you sign in to Microsoft:
- Go to Manage how you sign in to Microsoft and sign in.
- Under Account alias, find the current phone number.
- Select Remove next to the old phone number.
- If the phone number is the primary alias, extra steps are required before it can be removed.
- Select Add phone number and follow the prompts to add the new number.
If the new number is already linked to another Microsoft account:
- Sign in to the account that currently has that phone number.
- Select Remove next to the phone number.
- The number can only be removed if that account has another username on it.
- Sign out.
- Sign in to the account that should use the number.
- Select Add phone number.
If a message says the number is linked to a different account and it was only recently added there, the available option is to use a different mobile number by selecting Change number.
If this is a Microsoft 365 admin account and the goal is to update the admin contact phone number, use the Microsoft 365 admin center:
- Go to the Microsoft 365 admin center and sign in.
- Go to Users > Active users.
- Select the admin account.
- Under Contact information, select Manage contact information.
- Update the phone number and select Save changes.
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