Why My Android Phone Keeps Restarting (And How to Fix It)

 

You're in the middle of something important — a call, a message, maybe a video you were actually enjoying — and then your Android phone just restarts. On its own. Without warning. And you have no idea why.

It's frustrating. And honestly, a little alarming.

But here's the thing: a phone that keeps restarting on its own is almost always trying to tell you something. There's a reason behind it, and in most cases, that reason has a fix. You don't need to panic, and you definitely don't need to rush to a repair shop just yet.

In this guide, we're going to walk through every common cause of random Android restarts — and exactly what you can do to stop it for good.

Why Does My Android Phone Keep Restarting By Itself?

Before we jump into fixes, it helps to understand what's actually happening. Your Android phone restarts on its own when something forces the system to shut down and reboot — this could be a software glitch, a hardware issue, or something running in the background that your phone simply can't handle.

The good news? Most causes are fixable right from your phone, no technician needed. Let's go through them one by one.

1. Your Phone Is Overheating

Heat is one of the most common reasons an Android phone restarts suddenly. When your phone gets too hot, the system shuts itself down automatically to protect the processor and battery from damage. It's actually a safety feature — but it's one that signals something is wrong.

This happens more often during heavy use:

Gaming for long periods, recording video, or leaving your phone in direct sunlight. Samsung Galaxy users often notice this during extended use of high-performance apps, and Oppo or Realme users may see it when charging and using the phone at the same time.

What to do: 

Stop using the phone for a few minutes and let it cool down. Remove the case if you're using one, as it can trap heat. Avoid charging and using your phone simultaneously. If overheating happens regularly, read our detailed guide on why your Android phone gets hot and how to fix it.  Also check which apps are consuming the most power by going to Settings → Battery. 

On Samsung, you can also go to Settings → Device Care → Diagnostics to run a quick check.

2. A Faulty or Overloaded App Is Causing It

Sometimes one badly coded or crashed app is all it takes to send your phone into a restart loop. This is especially common after installing a new app — if the restarts started around the same time you downloaded something, that app is likely the culprit.

On Samsung devices, you may notice the phone restarting after opening a specific app from the Galaxy Store. Xiaomi and Redmi users sometimes experience this with third-party apps that conflict with MIUI's system processes.

If apps keep causing problems, check out our article on why Android apps keep crashing and how to fix it.

What to do:

 Think about any app you installed recently before the problem started. Uninstall it and see if the restarts stop. You can also boot your phone into Safe Mode, which disables all third-party apps temporarily. 

On most Android phones including Samsung, press and hold the power button, then long-press Power off until the Safe Mode option appears. If your phone stops restarting in Safe Mode, a third-party app is definitely the problem.

3. Your Storage Is Almost Full

A phone with almost no storage left behaves strangely — and random restarts are one of the symptoms. When your system doesn't have enough space to write temporary files or run basic processes, it can crash and reboot.

A full storage also causes freezing — read our guide on why your Android phone keeps freezing.

This is very common on budget Oppo, Realme, and Redmi phones that come with 32GB or 64GB of storage, which fills up quickly with photos, videos, and app data.

What to do: 

Go to Settings → Storage and check how much space is left. If you're below 1–2GB of free space, that's your problem. Delete unnecessary photos and videos, clear app caches, and uninstall apps you no longer use. 

On Samsung, Settings → Device Care → Storage gives you a smart cleanup option in one tap. On Xiaomi, use the built-in Cleaner tool inside the Security app.

4. A Corrupted or Incomplete System Update

Software updates are supposed to make your phone better — but sometimes an update that didn't install properly can cause serious instability, including random restarts. This can happen if the update was interrupted midway, or if the update itself had a bug.

Samsung users experienced this with certain One UI updates, and Oppo users have reported it after ColorOS updates as well.

What to do: 

First, check if another update is available that might fix the issue. Go to Settings → Software Update and download any pending update. If no update is available, try clearing the cache partition. 

On Samsung, power off your phone, then hold Volume Up + Power button together to enter Recovery Mode, and select Wipe Cache Partition. This clears temporary system files without deleting your personal data.

5. Battery or Charging Problems

An old, swollen, or damaged battery can cause your phone to shut down and restart unexpectedly — especially when the battery level drops suddenly or the phone can't draw stable power. If your phone restarts mostly when the battery is below 20%, or while charging with a cheap third-party cable, this is likely your issue.

This is particularly common in older Samsung Galaxy models and Redmi phones that have been in use for 2–3 years.

What to do:

 Try using only the original charger and cable that came with your phone. Avoid cheap third-party chargers as they deliver unstable voltage. If your battery drains unusually fast alongside the restarts, your battery may need replacement. 

On Samsung, you can check battery health under Settings → Device Care → Battery. If the battery is swollen or your phone's back cover is lifting slightly, visit a service center immediately.

6. Malware or a Virus

If your phone is showing ads randomly, apps are opening by themselves, and you're also getting unexpected restarts — malware could be behind all of it. This usually happens after installing apps from outside the Play Store, or clicking suspicious links.

Also review your installed apps and remove anything unfamiliar. Malware on Android is more common than people think, and random restarts are one of the early warning signs. 

What to do: 

Run a scan using a trusted security app. On Samsung, the built-in Device Care includes a basic malware scanner powered by McAfee — go to Settings → Device Care → Device Protection. 

For deeper scanning, install Malwarebytes from the Play Store. Also review your installed apps and remove anything unfamiliar. We've covered this topic in full detail in our article on how to tell if your Android phone has been hacked — if you're seeing other suspicious signs alongside the restarts, that's your next read.

7. A Hardware Problem

If none of the software fixes above have worked, the issue may be physical. A loose battery connection, damaged charging port, or internal component failure can all cause random restarts. Dropping your phone or exposing it to moisture can also cause hardware-level instability that shows up as restarting.

What to do: 

Check if your phone restarts more when you press on the back or sides — this can indicate a loose battery or internal connection. If your phone has been dropped or exposed to water recently, take it to an authorized service center.

 For Samsung users, Samsung Members app has a built-in diagnostics tool that can help identify hardware issues before you visit a shop. 

8. Factory Reset (Last Resort)

If you've tried everything above and your phone is still restarting on its own, a factory reset may be the only remaining option. This wipes your phone completely and restores it to its original state — which eliminates any software corruption that may be causing the problem.

What to do: 

Before you reset, back up everything — your photos, contacts, and important files. On Samsung, use Smart Switch to create a full backup.

 On Xiaomi, use Mi Cloud. 

On Oppo and Realme, use their built-in backup tool under Settings → Additional Settings → Backup and Reset.

Management → Reset → Factory Data Reset on Samsung, or Settings → Additional Settings → Backup and Reset

on Oppo/Realme/Xiaomi. Confirm and let the process complete. Set up your phone fresh and see if the restarts are gone. 

Frequently Asked Questions

Q. 1: Why does my Android phone keep restarting by itself?

Usually it's overheating, a bad app, low storage, or a software glitch. Go through each cause one by one to find the exact problem.

Q. 2: Can a virus cause my Android phone to restart?

Yes. Malware can disrupt system processes and trigger unexpected restarts. Run a security scan and remove any suspicious apps immediately.

Q. 3: Why does my Samsung phone keep restarting after an update?

The update may have installed incorrectly. Download the latest available update or clear your cache partition through Recovery Mode.

Q. 4: Will factory reset fix random restarts on Android?

In most cases yes. It removes software corruption and gives your phone a fresh start. Always back up your data first.

Q. 5: Why does my phone restart when the battery is low?

Your battery is likely worn out and can't hold a stable charge. If your phone is 2–3 years old, consider getting the battery replaced.

Q. 6: Is it bad if my Android phone keeps restarting?

Occasional restarts are normal. But frequent random restarts mean something is wrong and should be fixed before it gets worse.

Final Thoughts

A phone that restarts on its own doesn't have to mean the end of your device. In most cases, it's something you can fix yourself — whether it's clearing some storage, uninstalling a bad app, or updating your software. The key is to go through the causes one by one rather than jumping straight to panic mode.

Start with the simplest fixes first — storage, apps, overheating — and work your way down the list. Chances are you'll find your answer before you even reach the factory reset option.

And if your phone is still misbehaving after all of this, at least you'll know you've tried everything possible before handing it over to a technician.