iPhone alarm not going off? 8 things to check

2 min read · 8 steps · Updated 2 October 2026

Short answer

Open the Clock app and check the alarm is switched on, set for the right days and has a sound that is not None. Then raise Ringtone and Alerts under Settings, Sounds & Haptics. Silent mode and Do Not Disturb do not mute alarms, but a volume of zero does.

Clock alarms on an iPhone are designed to sound even in Silent mode and during a Focus. When one fails, it is almost always the alarm volume, the chosen sound or the schedule.

Step by step

  1. Check the alarm is on and set for today

    Open Clock, Alarms. The switch must be green. Tap the alarm and look at Repeat: an alarm set for weekdays stays silent at the weekend.

  2. Check AM and PM

    On a 12-hour clock, 7:00 PM instead of 7:00 AM is the classic mistake.

  3. Check the alarm sound

    Tap the alarm, then Sound. If None is selected, the alarm only vibrates. Pick a ringtone and scroll to the top to check Haptics as well.

  4. Raise the alarm volume

    Open Settings, Sounds & Haptics and drag Ringtone and Alerts to the right. Clock alarms use this slider, not the media volume. Turn off Change with Buttons so you cannot lower it by accident.

  5. Turn off Attention Aware Features for a test

    On Face ID iPhones, the alarm gets quieter when the phone sees you looking at it. If it seems too quiet, switch this off under Settings, Face ID & Passcode.

  6. Disconnect headphones and speakers

    Alarms play on the iPhone speaker, but a stuck Bluetooth connection can cause odd behaviour. Switch Bluetooth off overnight as a test.

  7. Look at the Sleep schedule

    A wake-up alarm set in Health or under Clock, Alarms, Sleep has its own sound and volume. Tap Change and check them.

  8. Restart and update

    Restart the phone and install any iOS update. Delete the alarm and create a new one if it still fails.

Good to know

Do not rely on a third-party alarm app for something important. Other apps can be muted by Silent mode and Focus; the built-in Clock alarm is not.

The phone must be switched on for an alarm to sound. It does not turn itself on.

Test it: set an alarm two minutes ahead, lock the phone and wait.

In short: Alarm on, right days, a real sound, and Ringtone and Alerts volume up.

Sources
  • Apple Support: How to set and change alarms on your iPhone

Rules and prices change. Check the official source before you act.