
Samsung: fast charging doesn't work – you can do that
Fast charging doesn't work on your Samsung smartphone? You may have to set the function first, but there may also be other errors. In this guide you will learn what to do if you have problems with fast charging.
Set fast charging
Fast charging and fast inductive charging are options for Samsung smartphones. They are enabled at the factory, but you may have accidentally disabled them. It is best to have a look to be on the safe side: "Device maintenance> Battery> Charging> Fast charging". Flip the "Fast Charging" switch so that it has a blue background, and also the "Fast Inductive Charging" switch, if applicable. This means fast wireless charging.

You can activate fast charging in the settings. Image: © Samsung / Screenshot: 2021
Connect the smartphone to the power adapter and check whether fast charging works now. If not, reboot and try again.
Use a suitable fast-charging power supply
Fast charging only works with a suitable power supply unit. Maybe you have connected your Samsung smartphone to an old, weaker power adapter and that's why it doesn't fast-charge. Fast charging adapters can also be used with lower wattage cell phones – but the reverse does not work.

This is what the original 25-watt power supply unit with "Super Fast Charging" from Samsung looks like. Image: © Samsung 2021
Samsung offers 45-watt, 25-watt, and 15-watt power supplies for fast charging. These can be used with all possible cell phones, but can only be used with the following devices:
- 45 watts : Galaxy S10 Lite, Galaxy Note10, Galaxy Note10 +, Galaxy S20 Ultra 5G
- 25 watts : Galaxy S10 5G, Galaxy A80, Galaxy A70 and newer (including Galaxy S20, Galaxy S21)
- 15 watts : Galaxy S7 to S10, Galaxy Note 8 and Note 9, Galaxy A50 and newer, Galaxy M21 and newer
The optional fast charging power supply with 45 watts is designed for four Samsung smartphones. The Galaxy S21 Ultra 5G is satisfied with a 25-watt power supply, perhaps Samsung has said goodbye to 45-watt fast charging for newer devices. Instead, the manufacturer relies on a 25-watt power supply for its flagships as of 2021, which is also compatible with upper-middle-class models.
Older flagships from the Galaxy S7 and newer entry-level to mid-range models usually rely on fast charging with a 15 watt power supply. If necessary, refer to the operating instructions to see whether your smartphone can be used with a quick-charging power supply unit and which one is the fastest for charging.
In this regard, it is often recommended that you only use official Samsung accessories. You can be sure that this will work with your Samsung phone, but valuable third-party accessories are also an option. Pay attention to the compatibility with your Samsung smartphone as well as to tests, customer ratings and brands that you trust.
Use a different cable or power supply
If fast charging does not work, this could also be due to an incompatible third-party power supply. Or on a defective power supply. Try charging with an original, intact power adapter. The USB cable could also be defective – try another one.
Turn off the smartphone while it is charging
An activated display consumes electricity and the smartphone charges faster when you switch it off. Fast charging as such should also work with the display activated, but not at the same speed.
Clean the charging port

Is the USB port (here from the Google Pixel 5) clean? Picture:
Fast charging may not work because the charging port on your Galaxy phone is dirty. If the cable is properly plugged into the cell phone and has no loose connection, dirt could also be the problem and cleaning is appropriate. Remove the cord and use a flashlight to check the connector for contamination.
Carefully (!) Remove the dust with a toothpick or tweezers. If necessary, you can also try your luck with a cotton swab soaked in alcohol. Make sure to let the connector dry before you reconnect it to the power supply. This should take about an hour – check with the flashlight that the connection is dry.
Perform an Android update
You should always install the latest system updates. The smartphone will automatically find out whether there is a new update and notify you. Updates are also used for troubleshooting – and maybe the fast loading that doesn't work is just such a bug. To check whether your Samsung mobile phone is up-to-date and, if necessary, to update it manually, go to "Settings> Software update> Download and install".

You can also install a system update manually. Image: © Samsung 2021
Clear the temporary storage / system cache
Android uses temporary files in the cache to load apps faster. Updates and app installations can affect the cache, even if this is not the normal case. If the other solutions described above don't work, clearing the cache is an option. To do this, proceed as we did in the Samsung Galaxy S6, S7 or S8 guide that no longer works: This has to be done under "Clear system cache".
See if an app is causing the problem
Sometimes the fast loading error could be caused by an app messing up the operating system. You can check whether this is the case by starting the system in "Safe Mode".
- Press and hold the power button for a few seconds.
- Press and hold the "Power off" button in the menu for a few seconds.
- Tap on "Safe Mode".

The Safe Mode option temporarily disables downloaded apps. Image: © Samsung / Screenshot: 2021
The smartphone now starts in safe mode, which has the advantage that downloaded apps are temporarily deactivated. Test that fast charging works in safe mode. If so, one of the recently installed apps is triggering the error. Uninstall it and try fast loading again.
Calibrate the operating system and battery
Android may not be able to record the actual charge level and the correct charging speed. To make it work properly again, do the following:
- Empty the battery completely until it reaches 0 percent.
- Charge the Samsung smartphone completely to 100 percent.
- Unplug the USB cable from the phone.
- Reboot.
- Use the phone until it's empty.
- Repeat these steps.
Reset the smartphone to the factory settings
If the problem cannot be clearly identified, resetting the smartphone to the factory settings may help. Please note, however, that this will erase all data from the phone memory , including the Google account, app data, settings, music, pictures and everything else.
- Go to "General Management> Reset> Factory Reset".
- Confirm your choice with "Reset".
- Set up the smartphone again after the restart. Try fast charging now.

Factory resetting is an idea as a last resort. Image: © Samsung / Screenshot: 2021
Take your Samsung phone for repair
If all of this does not help and the quick charge function is important to you, you should take your Samsung smartphone for repair.
SATURN offers a repair service for smartphones .