Restarting once in a while versus a loop
An iPhone that restarts now and then, and is otherwise usable, is the case this page covers. One that never gets past the Apple logo is a different problem with its own steps: iPhone stuck on the Apple logo and recovery mode.
Read the crash logs
Settings → Privacy & Security → Analytics & Improvements → Analytics Data lists the phone's logs. Files whose names start with panic-full and carry today's date are the restarts. Their number tells you how often it happens; their contents are technical, but a few words in them are telling.
If the logs mention missing sensors, and the phone restarts roughly every three minutes, a part has stopped responding — commonly the charging port assembly or the battery — and the steps below will not help. That pattern needs a repair.
Update iOS and your apps
A restart triggered by a bug is the most common software cause, and Apple fixes them in point releases. Install any update in Settings → General → Software Update — our update guide covers it — and update apps from the App Store.
If the restarts began after installing a particular app, or happen when you open one, delete it and watch whether they stop.
Free up storage
An iPhone with almost no free space struggles to write the files the system depends on, and can restart under the strain. Settings → General → iPhone Storage shows what is left; a few gigabytes free is a sensible minimum. Freeing up space covers the quickest wins.
Check the battery
A worn battery can no longer deliver the bursts of power the processor demands, and the phone shuts down or restarts under load — opening the camera, starting a game, in the cold. Settings → Battery → Battery Health shows whether iOS has seen this happen; a note about unexpected shutdowns there means the battery is the cause. See how to check battery health.
Reset settings, then restore
Settings → General → Transfer or Reset iPhone → Reset → Reset All Settings returns every setting to its default without touching your data. It rules out a configuration problem.
If restarts continue, back the phone up and erase it, then test it as new before restoring the backup. A phone that restarts even when set up fresh has a hardware fault; one that only restarts with your backup restored has a software one, which an app or setting in it carries. How to factory reset an iPhone walks through it.
When it is hardware
Restarts that continue on a freshly erased phone, panic logs that name missing sensors, restarts after a drop or liquid exposure, and restarts that stop only while the phone is connected to power all point at hardware. The battery and charging port are the most common parts at fault, and both are routine repairs.
Frequently Asked Questions
Why does my iPhone keep restarting?
A software bug, an app, nearly full storage, a worn battery, or a failing part. The panic-full logs in Settings → Privacy & Security → Analytics & Improvements → Analytics Data show how often it happens.
Why does my iPhone restart every 3 minutes?
That pattern almost always means a part has stopped responding — commonly the charging port or the battery — and the phone needs a repair.
Will updating iOS stop my iPhone from restarting?
If a bug is the cause, often yes. Install the latest update and update your apps first.
Does Reset All Settings delete my data?
No. It returns settings to their defaults — Wi-Fi passwords, wallpaper, privacy choices — and leaves photos, messages and apps alone.