How to Fix iPhone Keeps Restarting After iOS 18 Update 2025

Part 1. Why does My iPhone Keep Restarting after iOS 18 Update?

If your iPhone keeps restarting after the update, you're likely facing one of several common issues that can arise with new software installations. These problems are not unusual, especially with updates, which are often more prone to bugs and compatibility issues.

• Software Bugs: New software updates aren't always flawless. Sometimes, bugs can sneak in and cause crashes that lead to iOS 18 random restart. These bugs can be with the update itself, or how it interacts with your specific iPhone's hardware and software.
• Incomplete Update: If the update process gets interrupted for some reason, like a weak internet connection or your phone running out of battery, it might leave your iPhone. This glitch can cause unexpected restarts.
• Incompatible Apps: Some apps may not yet be optimized for the new iOS version, leading to conflicts that make the iPhone keeps restarting iOS 18.
• Insufficient Storage: Another reason behind iOS 18 restart is insufficient space. When your phone doesn't have enough space to breathe, it might restart to free up temporary resources.

Part 2. What to Do When Your iPhone Keeps Restarting?

If your iPhone keeps restarting after update, don’t worry! We’ve got the solution.

Fix 1. Force Restart iPhone

A force restart is a quick and straightforward method to resolve many minor software issues that might be causing your iPhone to keep restarting after the update. This process forces your device to shut down and reboot, clearing any temporary glitches without affecting your data.

Follow these steps to force restart your iPhone: (for iPhone 8 and Later)

• Quickly press and release the Volume Up button.
• Quickly press and release the Volume Down button.
• Press and hold the Side button until the Apple logo appears, then release the button.

Fix 2. [Recommended] Fix iPhone Keeps Restarting After iOS 18 Update in One-Click

While a force restart is a great first step, sometimes a more robust solution is needed. If your iPhone keeps restarting after iOS 18 update even after trying the first fix, consider using Tenorshare ReiBoot. This user-friendly iOS repair tool offers a one-click solution specifically designed to address over 150 iOS system issues.

The clear interface makes it easy for anyone to navigate, and the dedicated repair function tackles the problem directly, fixing it in a single click. Importantly, Tenorshare ReiBoot prioritizes data safety, so you can fix your iPhone without losing any data. Just follow these simple steps.

• Install Tenorshare ReiBoot on your computer (Windows or Mac) and connect your iPhone with the computer. ReiBoot will automatically detect your device. Once detected, click “Start Repair.”

• Choose “Standard Repair.”

• ReiBoot will suggest a firmware for your iPhone model. Click “Download” and wait for the firmware to download.

• You can then click on “Start Standard Repair” and a repair process will initiate. Wait until ReiBoot does its magic and your iPhone restarts automatically.

• Click “Done” when finished.

Fix 3. Restore iPhone via iTunes

You can also try restoring your iPhone via iTunes to fix the underlying issues. This process completely wipes your iPhone and reinstalls the latest iOS version, potentially eliminating any software bugs or corrupted data..

However, unlike Tenorshare ReiBoot, this method will erase all your data, so make sure you have a recent backup before proceeding. Here’s how to fix iPhone randomly restarts iOS 18 via iTunes.

• Open iTunes on your computer and connect your iPhone with it. Make sure you’ve installed the latest version.
• Put your iPhone into Recovery Mode. To do that, press and release the volume up button, then the volume down button. Then press and hold the power button until the screen goes black.
• iTunes will detect the problem with your iPhone and ask you to Restore it. Confirm and iTunes will begin fixing your iPhone.

Fix 4. Remove SIM Card

In some cases, a faulty connection with your carrier network can contribute to iOS 18 iPhone keeps restarting. Here's a simple fix you can try: removing your SIM card. Here’s how:

• Completely shut down your iPhone by holding the side button and then swiping the power off slider.
• Locate the SIM card tray. It's usually on the side of the device. You might need a SIM ejector tool (which often comes with your iPhone) to open the tray.
• Carefully insert the SIM ejector tool into the small hole next to the SIM card tray. Push firmly but gently until the tray pops out.
• Gently lift the SIM card out of the tray and leave the SIM card out for a few seconds.
• Place the SIM card back into the tray, making sure it's in the correct orientation. Now gently push the SIM card tray back into the slot on your iPhone until it clicks into place.

Fix 5. Contact Apple Support

If the above-mentioned solutions haven’t worked to fix your iOS 18 iPhone restarting issue, contacting Apple Support can provide you with expert assistance and more advanced troubleshooting options to resolve the issue.

• Head over to https://support.apple.com/.
• In the search bar, type "iPhone keeps restarting after iOS 18 update." This should lead you to relevant support articles or troubleshooting steps.
• If the search results don't solve your problem, look for the chat option on the Apple Support website. You can chat with a support representative who can diagnose the issue and offer further assistance.

Part 3. People Also Ask about iPhone Keep Restarting after iOS 18 Update

Q1. Can a bad battery cause an iPhone to keep restarting?

A weak battery can definitely be behind your iPhone's restarts after the iOS 18 update. A weak battery can definitely be behind your iPhone's restarts after the iOS 18 update. If your iPhone is behaving weirdly, like restarting after you charge it, this could be because your battery is either not calibrated or has degraded. Checking your battery health in the settings and considering a battery replacement if necessary can help resolve this issue.

Q2. What happens when your iPhone keeps restarting?

When your iPhone keeps restarting, it can be frustrating and disruptive. The most common scenario is unexpected restarts throughout the day, interrupting your tasks and forcing you to reopen apps. In the second case, the iPhone keeps restarting during a restore process. This can occur if there is an issue with the software being restored, or if the device encounters a critical error during the process.

Conclusion

If your iPhone keeps restarting after iOS 18 update, you can address the issue and get your iPhone back to normal using the tips mentioned in this article. For a quick and reliable fix, we recommend using Tenorshare ReiBoot. This tool is a great choice for fixing your iPhone's restart issue because it's simple to use, effective, and safe. With Tenorshare ReiBoot, you can resolve the problem in just a few clicks, ensuring your iPhone runs smoothly again.