Why don’t calendar reminders wake you up?

Why does my calendar reminder make no sound?

Because it is following the rules you gave your phone. When Silent Mode is on, notification sounds are suppressed system-wide, and a calendar alert is a notification like any other. Focus goes further and can stop the banner from appearing at all, so there is nothing to see and nothing to hear. Which alerts survive a Focus and which do not is set out in what Focus mode does to calendar alerts.

This is why the problem gets worse the more disciplined you are. People who silence their phone to concentrate are exactly the people whose reminders never arrive. The same mechanism is behind silent Google Calendar notifications and Outlook reminders that never ring on iPhone.

What actually rings through Silent Mode?

Alarms, timers, and calls from people you have allowed through. That is the short list. An alarm you set in the Clock app rings at full volume with the phone on silent, which is the behaviour you want for a meeting you cannot miss. On iOS 26.1 and later an app can schedule that same class of alarm, which is what Pealo does on iPhone for every event it reads.

How many alarms would you set by hand?

Take an ordinary week with 14 meetings across a work calendar, a personal one and a university one. Setting an alarm for each takes about 25 seconds including finding the right time, so that is roughly 6 minutes a week and 5 hours a year — assuming you remember every single one. The forgetting is the expensive part, not the tapping.

So what should you use?

If you have two or three fixed meetings a week, manual alarms in the Clock app are fine. If your calendar changes daily, or you keep more than one account, an app that reads the calendar and arms the alarms for you removes the step where you forget. There is a side-by-side comparison of the calendar alarm apps if you want to see which accounts each one can read.