Your iPhone can play a short sound when you lock the screen. If that sound is turned off, you can enable it from the Sounds & Haptics settings.
How to Turn On the iPhone Lock Sound
- Open Settings.
- Tap Sounds & Haptics.
- Scroll down and turn on Lock Sound.
After you enable the setting, lock the iPhone with the side button to test it.
If You Still Don’t Hear the Lock Sound
Check the iPhone’s sound settings and ringer/alert volume. Apple groups alert and system-sound controls under Sounds & Haptics, and the volume buttons can control ringer and alert volume unless that behavior is locked in Settings.
If the setting is on but the sound is still missing, raise the Ringtone and Alerts volume in Sounds & Haptics, then restart the iPhone and test again.
Lock Sound vs. Keyboard Sound and Haptics
The Lock Sound setting is separate from keyboard feedback. Keyboard sounds and haptics are controlled under Settings > Sounds & Haptics > Keyboard Feedback. Turning keyboard sound off does not automatically disable the lock sound.
Can You Change the Lock Sound?
iOS does not provide a normal setting for selecting a custom lock sound. You can turn the system lock sound on or off, but you cannot choose a different built-in sound for that action.
Summary
To enable the iPhone lock sound, open Settings, tap Sounds & Haptics, and turn on Lock Sound. If you still cannot hear it, check the ringer/alert volume and restart the iPhone. The setting is separate from keyboard sounds and haptics.