Why do you sometimes need your passcode instead of FaceID?

[Cunir]

I've got FaceID on my phone but every 4-5 days or so I'll be trying to pay for something in a shop and it will suddenly insist on having my passcode instead. And I've got 'unlock with my watch' turned on as well. It still wants the code.

I'm a bit paranoid about entering my passcode in public so this is a bit annoying.

I totally get that it will need your passcode after an update, and stuff like that, but why does it randomly want it out of the blue? Do you get a certain number of faceID logins before it wants the code again?

 

[Jackbequickly]

It is just Apple’s way of helping you to not forget your passcode. Both my iPhone and iPads will occasionally ask for me to re-enter my passcode. Happens maybe once a week.

 

[NoBoMac]

Happens maybe once a week.

Pretty much. 6.5 days is the time-out.

Face ID, Touch ID, passcodes, and passwords

To use Face ID or Touch ID on supported Apple devices, the user must set up their device so that a passcode or password is required to unlock it.

support.apple.com

The user hasn’t used their passcode or password to unlock their device for 156 hours (six and a half days)