iPhone Not Ringing on Incoming Calls
Missing one or two phone calls when your iPhone is switched off is no big deal. Missing many of them when it's on because it simply won't ring, however, is a problem, whether the calls are from your parents, your best friend or your crush. Figuring out the cause of the issue may take some time, but once you've done so you can make sure your iPhone is only silent when you want it to be and avoid any further awkwardness.
1 The Silent Switch
The iPhone has a switch, located on the left side directly above the volume buttons, that will silence all ringtones and alerts when toggled. It might be obvious, but it still bears checking -- you may have toggled it accidentally or forgotten about it. There is no on-screen indicator when your iPhone is silenced in this manner; when you receive a phone call, it'll still vibrate, but that won't help you if you are keeping it somewhere you won't notice the vibration.
2 The Volume Buttons
If the "Change With Buttons" switch in the "Sounds" section of the settings is set to "On," pressing the volume buttons on the side of your iPhone will increase and decrease the volume of ringtones and other alerts. Although the ringtones can't be completely silenced in this manner, they are just barely audible at the very lowest volume and are therefore very easy to miss. To check if this is the cause of your issue, open the settings and tap "Sounds" -- if the volume slider in the "Ringer and Alerts" section is all the way to the left, drag it all the way to the right, toggle the "Change With Buttons" switch off, and then ask a friend to call you to test if the issue is solved.
3 Do Not Disturb
If you don't want to be woken up by inconsiderate people calling you in the middle of the night, the iPhone's "Do Not Disturb" feature can be a Godsend. If you aren't aware it's on, however, it can be one of the most mystifying causes of your iPhone not ringing, especially if it's set to automatically switch on at a certain hour every day. Your iPhone will ring perfectly fine at times, but occasionally fail to let calls through. To check if this is the issue, open your iPhone's settings and tap "Do Not Disturb." Set both the "Scheduled" and the "Manual" switches to "Off" to eliminate the issue.
4 Other Causes
If you've tried everything and your iPhone still won't ring, the cause may be a hardware issue and you'll need to send it in to Apple or bring it to an Apple store for repair. You can check if this is the case by ensuring the iPhone's volume is set to the maximum and then launching an app that plays sound, such as the Music app or a game. The silent switch and the "Do Not Disturb" mode only affect ringtones and other alert sounds -- so if even app sounds won't play, you can be certain it's a hardware issue.
5 Article Disclaimer
Information in this article applies to iPhones running iOS 7. It may vary slightly or significantly with other versions.