I would like to remove my old work email account from the Authenticator

To remove the old work email account from Microsoft Authenticator, remove that account entry inside the app. If desired, all Authenticator data can also be cleared from the device.

To remove just the work account from Authenticator:

1. Open the Microsoft Authenticator app on the phone.
2. Select the work account that should be removed.
3. Tap the Settings gear for that account.
4. Tap Remove account and confirm.

Important: After removing the work account, that device will no longer be able to use Authenticator to verify sign-in for that work account.

If the goal is to completely sign out of Authenticator and remove all accounts:

On Android

1. Open the device Settings app and select Apps.
2. Select Authenticator from the app list.
3. Select Storage or Storage & cache.
4. Tap Clear data, then OK.

On iOS

1. Open the device Settings app.
2. Select General > Storage.
3. Select Authenticator from the app list.
4. Tap Offload App.

Important: Clearing data or offloading the app removes all accounts from Authenticator and cannot be undone. The device will no longer be able to verify sign-ins for any of those accounts until they are added again.

If the old work email is also listed as a sign-in verification method for a work or school account, it can be removed from the account’s security info by signing in to the account’s Security info page and deleting that email method there.

References:

• How to sign out from Authenticator
• Set up an email address as your verification method
• Removing a sign-in verification method