[rwc]

To enable the Unlock with Apple Watch feature, open the Settings app on your iPhone, then look for the “Face ID & Passcode” setting. Once you flip this toggle, your Apple Watch will be able to authenticate your iPhone as long as the following conditions are met:

- Face ID detects a mask - Your Apple Watch is nearby - Your Apple Watch is on your wrist - Your Apple Watch is unlocked - Your Apple Watch has a passcode enabled

https://9to5mac.com/2021/02/04/iphone-face-id-unlock-apple-w...

[judge2020]

I think the unknown is if it uses any face ID data as part of the unlock still, like a partial scan of the top of your face.

[quenix]

In my anecdotal experience, it does not. The logic goes:

- Assert that a face is present. - Is wearing mask? > If yes, proceed with Watch unlock (irrespective of top of face). > If no, attempt Face ID scan.