How to Change the Phone Number on Outlook (Microsoft Account)

Outlook uses your Microsoft account security info. Go to account.microsoft.com › Security, add the new phone number, verify it, then remove the old one.

Steps

1. Sign in at account.microsoft.com with your Outlook address.
2. Open Security and choose the option to manage how you sign in.
3. Select Add a new way to sign in or verify, then choose phone.
4. Enter the new number and the code Microsoft sends.
5. Remove the old number from the list.

Two different phone fields

Change the security info number if codes are the problem.

Lost the old number

If Microsoft insists on a code to the old number, choose I don't have any of these. Microsoft may let you add the new number with a waiting period, during which you receive notices at your other contacts. This protects you from someone else changing your details. See Outlook recovery.

Use the Authenticator app

Adding Microsoft Authenticator means you can approve sign-ins without texts, and a number change will not block you next time. See Microsoft two-step verification.

Work Outlook accounts

Outlook at work or school uses an organisation account. Change its phone at mysignins.microsoft.com under Security info, or ask IT.

Codes not arriving

• Check the country code.
• Wait before asking again.
• Try a call instead of a text.

See Microsoft code not sent.

Outlook app on your phone

Changing the security phone number does not sign you out of the Outlook app. You may be asked to sign in again on some devices. Keep your password handy, and approve the request in the Authenticator app if you use it.

Alternate email

Add an alternate email address in the same security info list. It gives Microsoft a second way to send you codes if the phone is lost.

Check after changing

Sign out and sign back in once on a computer to make sure the code arrives on the new phone before you give up the old SIM.

FAQ

How do I change my phone number on Outlook?

account.microsoft.com › Security, add the new number, remove the old.

What if I lost my old Outlook phone number?

Choose I don't have any of these and follow the steps.

Is the profile phone the same as the security phone?

No, only security info is used for codes.

Related: Outlook recovery · Microsoft two-step verification · close a Microsoft account.