This article will help you re-use mobile numbers connected with Microsoft accounts. The steps depend on the message shown when trying to sign in or sign up.

Phone number is already a Microsoft account

If you see the message "[phone number] is already a Microsoft account" when trying to create a new Microsoft account, it means that the phone number you entered is already associated with another Microsoft account. 

  • If your phone number is associated with a different Microsoft account, and you want to associate it with your new Microsoft account, select Sign up from the message and follow the prompts to remove it from the existing account and move it to the new account.

  • If the phone number is associated with another Microsoft account you own, you can use your phone number to sign in since it’s already a Microsoft account. Select Sign in from the message and follow the prompts.

Phone number is already used to sign in

If you see the message "We noticed [phone number] is already used to sign in to [another number]" when trying to add the number as an alias or as another username, it means that the phone number you entered is already associated with another Microsoft account. 

  • If your phone number is already an alias for another Microsoft account you own, you can use your phone number to sign in since it’s already a Microsoft account. Select Continue to sign in, without adding another phone number.

    Some Microsoft products and services require a phone number, so you should choose a different number to associate with your account if possible.

  • If yourphone number is an alias for a different account and you want to associate it with yourMicrosoft account, select Transfer number and follow the prompts.

  • If you don't see the transfer option, it's because the phone number has been recently used in another Microsoft account. Select Change number to choose a different number to associate with youraccount. If the phone number is new to you, try again after 30 days to see the Transfer option.

Need more help?

Email addresses and phone numbers associated with your Microsoft account are called aliases.

They use the same contacts, online storage, subscriptions, and account settings.

You can use any of your aliases to sign in to Microsoft services or your Windows and Xbox devices, and you can select any of them for sending and receiving email. 

Your aliases share a single password.

If you can't sign into your Microsoft account, or you've forgotten the email address or phone number used to sign in, use our guided tool below to help you find the correct solution.

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