Find your Settings app on your iPhone and select it.
Scroll down your settings to find Face ID & Passcode. Select it.
Enter your 4-digit passcode that you use to alternatively unlock your iPhone. (You'll be using this again once you deactivate Face ID.)
Here you can select and deselect whether you want to use Face ID for:
- iPhone Unlock (to unlock your iPhone from its unlock screen)
- iTunes & App Store (for any purchases in iTunes or Apple App Store)
- Apple Pay (if you have Apple Pay set up, you can use Face ID to pay for certain items)
- Password Autofill (Face ID will be used to verify your identity to autofill passwords at various websites)
Choose which options you want to use Face ID and which you'd like to turn off.
Sometimes, when you are busy or out and about and your iPhone starts ringing, you don't want to pick it up, but you know it might be so-and-so with that important call you've been waiting on.