The iPhone Lock Screen is designed to provide quick access to essential information and communication tools without requiring the user to fully authenticate via Face ID or a passcode. One of these default conveniences is the ability to return a missed phone call or FaceTime call simply by tapping the missed call notification on the Lock Screen. While convenient for the device owner, this poses an obvious physical security vulnerability. If an unauthorized individual gains temporary physical access to a locked iPhone, they can easily initiate a phone call to anyone who recently tried to contact the owner, potentially spoofing their identity or incurring long-distance charges.
This guide explains how to completely disable the “Return Missed Calls” feature on the iPhone Lock Screen, ensuring that physical access to the device does not equate to communication access.
Disable Return Missed Calls via Face ID Settings
To secure the Lock Screen, we must explicitly revoke the operating system’s permission to bridge the notification center with the telephony subsystem while the device remains in a locked state.
- Unlock your iPhone and open the main Settings app.
- Scroll down and tap on Face ID & Passcode (or “Touch ID & Passcode” on older models).
- You will be prompted to enter your device’s numeric passcode to proceed.
- Scroll down to the section titled Allow Access When Locked. This section governs which features bypass the encryption lock.
- Locate the toggle switch labeled Return Missed Calls.
- Toggle the switch to the Off (grey) position.
Verify the Configuration Lockdown
Toggling this switch immediately instructs the iOS kernel to block the tel:// URL scheme execution from any notification banner until the secure enclave verifies a successful biometric or passcode authentication.
To verify the lockdown is active, lock your iPhone screen. Have a colleague or a secondary device place a call to your iPhone, and let it ring until it registers as a missed call. Wake the screen to view the missed call notification banner. If you attempt to tap the banner, or long-press it to reveal interaction options, the iPhone will immediately demand Face ID authentication or prompt for your passcode before it initiates the dialing sequence. The device is now secure against unauthorized callback attempts.