How Face ID with a Mask Works on iOS 15

Apple introduced the ability to use Face ID while wearing a mask in iOS 15.4, allowing users to unlock their devices and authenticate payments without removing face coverings. This article outlines the technology powering this feature, which devices support it, how it identifies users through periocular recognition, and how to set it up.

The Underlying Technology: Periocular Recognition

Standard Face ID projects over 30,000 infrared dots to map the unique geometry of an entire face. When a user wears a mask, the nose, mouth, and jawline are obscured, rendering standard mapping ineffective.

To overcome this, Face ID with a mask relies on periocular recognition. The TrueDepth camera system and the A-series Neural Engine focus specifically on the unique, detailed features surrounding the eye area. This includes the contours of the eye sockets, the shape of the eyelids, skin folds, and bone structures around the brow. Because the available surface area is significantly smaller, the system requires higher processing power to maintain security standards.

Device Compatibility

Due to the intensive machine learning and processing power required to authenticate the periocular region accurately, the feature on iOS 15 is limited to newer hardware:

  • iPhone 12, 12 mini, 12 Pro, and 12 Pro Max
  • iPhone 13, 13 mini, 13 Pro, and 13 Pro Max
  • (Later models also support this feature, but older devices such as the iPhone 11 and iPhone X series do not).

Authentication Requirements and Glasses

Because the system depends entirely on the eye region, unobstructed visibility is critical:

  • Attention Awareness: The feature requires the user to establish direct eye contact with the display.
  • Eyeglasses: Users who wear regular prescription glasses can register them during setup. Up to four pairs of glasses can be added to improve accuracy.
  • Sunglasses: The feature does not support sunglasses. Because the eyes must be fully visible for periocular scanning, dark or polarized lenses block the necessary biometric data.

Security and Usability

Unlike the earlier "Unlock with Apple Watch" workaround introduced in iOS 14.5, native Face ID with a mask provides full biometric security parity with standard Face ID. It functions across the entire operating system, including:

  • Unlocking the iPhone
  • Apple Pay transactions
  • Password autofill in Safari
  • Third-party app authentication (such as banking and password manager apps)

How to Enable the Feature

  1. Open Settings on a compatible iPhone running iOS 15.4 or later.
  2. Tap Face ID & Passcode and enter your passcode.
  3. Toggle on Use Face ID with a Mask.
  4. Follow the on-screen prompts to perform a facial scan without a mask.
  5. If applicable, select Add Glasses to complete scans while wearing your eyewear.