How to Fix Samsung Galaxy S21 Battery Draining Overnight

Smartphones are evolving to maintain their battery level for days. But still, a few Samsung Galaxy S21 users are experiencing a battery drain on their smartphones every night.

Are you one of those users experiencing battery draining on your Samsung Galaxy S21? Then this guide is for you.

In this guide, we will give you 5 fixes to resolve the overnight battery draining issue.

Note: Solutions in this guide will work on any Samsung Galaxy S21 model (S21, S21 Plus, S21 Fe, and S21 Ultra models.)

Editor’s note: We created these instructions using a Samsung Galaxy S21 running Android 12. Depending on your device’s software version, some steps and menu positions may look slightly different.

Why Does My Samsung Galaxy S21’s Battery Drain Overnight?

Usually, battery draining happens when there is an active process consistently running in the background. Android system terminates such processes when there is over-usage of the battery.

But if the battery drains overnight that means one or many processes run in the background overnight, consistently.

These are the common reasons causing processes to keep running on your Samsung Galaxy S21:

• Weak or no cellular signals coming to your Samsung Galaxy smartphone.
• Bixby routines and other automation processes.
• Poorly optimized third-party apps.
• A recent software update.

Fix 01: Turn on Airplane Mode At Night

If you aren’t a busy person at night, this option is best for you. You can turn on Airplane mode when you go to sleep or when you don’t need your device during the night.

Note: However, when the Airplane mode is on, you won’t receive calls or text messages until it is turned off.

Fix 02: Select a Different Network

Poor network connection (poor signals) can significantly increase the battery draining of your Samsung Galaxy S21.

Check the signal bars on the screen. If the signal bars are low, you can change your network to resolve this issue and fix the battery draining:

1. Go to Settings then tap on “Connections”.
2. Inside the Mobile networks, tap on “Mobile networks”.

3. Now you will see a list of available networks, select a different one from what is already selected.

Fix 03: Turn Off Unnecessary Features

Features like Bluetooth, GPS, NFC & Nearby share can drain your Galaxy smartphone’s battery quickly. It is because these features have a higher battery consumption rate (except Bluetooth which has optimized for lower battery consumption).

Therefore, if you don’t use these features during the night, it is better to turn them off. This will help to reduce your device’s battery drain overnight.

Fix 04: Clear Cached Data

You can also clear the cache partition of your Samsung Galaxy S21 to fix the overnight battery draining.

Wiping the cache partition required you to boot your Samsung Galaxy S21 into recovery mode. Here is how you can do that;

1. Turn off your Samsung Galaxy S21 and plug it into a power source.
2. Press and hold the Volume up and Power buttons simultaneously until your device boots into recovery mode. Once you see the recover menu, release the keys.
3. Use the volume keys to navigate to the “wipe cache partition” option and press the power button.

4. Now select Yes & confirm the process by pressing the power button again

5. Once the wipe cache partition is done, you will see the recovery mode again. Then; Select “Reboot device now” and press the power button to reboot the device into normal mode.

Fix 05: Do a Factory Data Reset

If none of the above fixes worked to resolve the overnight battery drain issue on your Samsung Galaxy S21, the last option you are left with is resetting your device by clearing all of its data.

But before going to reset your Galaxy S21 entirely, you need to back up all the data of the device. Also, make sure your device has at least 70% battery level remaining.

1. Go to Settings.
2. Tap on “General management”
3. Select “Reset”.

4. Then, select “Factory data reset”.