Managing personal Outlook.com account settings, security, and privacy
For a personal Microsoft account, adding a new phone number as a new sign-in verification method may no longer be available. On the Security page, the available options can be limited to a recovery email address, Microsoft Authenticator, or a passkey.
To check what can be added:
- Sign in to your Microsoft account Security tab at https://account.microsoft.com/security.
- Select Manage how I sign in.
- Select Add a new way to sign in or verify.
- If Phone is available, add the new number and complete the verification code prompt.
- If Phone is not available, use one of the available methods instead, such as a recovery email address, Microsoft Authenticator, or a passkey.
If the goal is to use a phone number as a sign-in alias, only one mobile number can be used as a sign-in alias for a Microsoft account.
If a message appears saying the number is already associated with another Microsoft account:
- If both accounts are owned, sign in to the account that currently has the number, remove it there, sign out, then sign in to the target account and add the number.
- If Transfer is shown, use Transfer number and follow the prompts.
- If Transfer is not shown, the number was recently used on another account. Use Change number and try a different number, or try again after 30 days.
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