iOS · iPhone & iPad
How to Troubleshoot an iPhone That Keeps Restarting
Source-checked About 10 minutes
Answer
Document when the restarts occur, update iOS, review storage and Battery Health, and arrange Apple service when the problem persists. Random restarts can have software, battery, temperature, accessory, or hardware causes, so no single generic toggle is a guaranteed fix.
Record the pattern before changing anything
Note the charge level, temperature, connected accessories, foreground app, and whether the iPhone restarts under load or while idle. Preserve the exact time of two or three events for support instead of assuming every restart has the same cause.
Restart normally once
Turn the iPhone off and back on with the normal model-appropriate button sequence. Use a force restart only when the device is frozen or unresponsive, not as a repeated repair routine.
Install the current iOS update
Open Settings > General > Software Update, back up important data, and install the current stable update when one is offered. Recheck for the same restart pattern after background update work has finished.
Review Battery Health
Open Settings > Battery > Battery Health on current models, or Battery Health & Charging where that older label remains. Review Peak Performance Capability and any Service or significantly degraded message.
Check available storage
Open Settings > General > iPhone Storage. Remove or offload content you recognize when storage is nearly full, but do not delete app data or backups without confirming what will be lost.
Test without a suspect accessory
If the pattern began with a charger, cable, adapter, or other accessory, disconnect it and test with known-good Apple-compatible equipment. Stop using anything damaged, unusually hot, or physically swollen.
Escalate persistent restarts
Back up the iPhone, then arrange Apple support or service if restarts continue, Battery Health recommends service, or the device overheats, will not stay on, or shows signs of physical battery damage.
Video walkthrough
If it does not work
- If Settings shows Service next to Battery Health, treat replacement as a service decision; do not attempt to open or replace an iPhone battery without the appropriate training and parts.
- If restarting began immediately after an update, allow background work to finish and record whether it continues; do not erase the iPhone before Apple support reviews the evidence.
Sources and verification
Checked against official documentation on . Scope: iPhone & iPad.
Follow the linked first-party guidance if labels differ after a platform or app update.