Samsung Galaxy battery draining fast? 6 fixes

What changed: every step re-shot on our own Galaxy S26 (Korean model SM-S942N) on One UI 9, dark mode, with the steps rewritten for the One UI 9 screens.

howtosimply.com/guides/samsung-galaxy-battery-draining-fast-6-fixes/ · Checked October 2026 · SM-S942N, Korean model), One UI 9, Android 17 (build S942NKSS4BZIG · Samsung Galaxy S26

12 of 12 steps with real screenshots · 2 official sources below

Device

Android

Shown on

Samsung Galaxy S26 (SM-S942N, Korean model), One UI 9, Android 17 (build S942NKSS4BZIG)

App

Settings

Path

Settings › Battery: check usage

Real screenshots

12 of 12 steps

Checked

October 2026

Sources

2 official, linked below

Step by step

1. 

   See what is using the battery

   Open Settings, Battery. The graph shows daily use this week and the list below shows each app. Ours read Battery usage: 2%, with Google Play services at the top. Tap View details for more.

   Watch these steps Done

2. 

   Read Usage by apps and features

   View details opens Battery activity. Pick a day at the top; Usage by apps and features lists each app with its screen time.

   Done

3. 

   Open Background usage limits

   Back on the Battery page, below Power saving, tap Background usage limits.

   Done

4. 

   Put unused apps to sleep

   Turn on Put unused apps to sleep. It was on on ours. Apps you have not used for a while are then limited in the background.

   Done

5. 

   Add apps to Sleeping or Deep sleeping

   Tap Sleeping apps or Deep sleeping apps, then + at the top right, and add apps you rarely open. Both lists were empty on ours. Never auto sleeping apps is for apps that must stay awake, such as a messenger.

   Done

6. 

   Open Device care

   Open Settings, Device care. On One UI 9 the top card just says Great! Your phone is running smoothly; there is no Optimize now button.

   Done

7. 

   Clean memory

   Tap Memory, then Clean now. On ours it offered +2.1 GB.

   Done

8. 

   Lower the brightness

   Open Settings, Display and drag the Brightness slider to the left. Adaptive brightness, just below, was on on ours; leave it on so the phone dims itself in the dark.

   Done

9. 

   Shorten the screen timeout

   Further down Display, tap Screen timeout. Ours was set to 30 seconds; Samsung suggests 1 minute or less to save battery.

   Done

10. 

    Turn on Power saving

    Settings, Battery, Power saving, then the switch at the top; ours showed Off. Standard limits background network use, syncing and location checks; Maximum limits everything except the apps you choose.

    Done

11. 

    Uninstall the app that drains

    If one app uses far more battery than the rest, open Settings, Apps, the app, and tap Uninstall at the bottom.

    Done

12. 

    If it only shows Disable

    Apps that came with the phone cannot be uninstalled. On ours, YouTube showed Open, Disable and Force stop; tap Disable to switch it off instead.

    Done

What changed: every step re-shot on our own Galaxy S26 (Korean model SM-S942N) on One UI 9, dark mode, with the steps rewritten for the One UI 9 screens.

Watch these steps

If you do not see this option

• No Device care in Settings? Tap Search in Settings and type Device care.
• Looking for Optimize now? One UI 9 has no Optimize now button on the Device care page (step 6). Use Memory, Clean now instead.

If this does not work

• Messages arrive late after you put apps to sleep Add the messaging app to Never auto sleeping apps under Background usage limits.
• The battery still drains fast Open Samsung Members, Support, Phone diagnostics and run the Battery status test. On ours it reported Normal, Life: Good.

About this guide

A Galaxy that used to last all day and now does not usually has one app working in the background, or a radio that searches all the time. These fixes follow the order of Samsung's own advice, quickest first.

The screenshots are from our Samsung Galaxy S26, the Korean model SM-S942N, with One UI 9 and Android 17 (build S942NKSS4BZIG), in Dark mode. Menus can differ on models sold in other regions. We cleaned memory once and changed no settings.

Good to know

Turn off Wi-Fi, Bluetooth or location in the quick panel when you are not using them.

To make the battery last longer over the years: how to limit charging to 80% on a Samsung Galaxy phone. Quick help for today: how to turn on Power saving on a Samsung Galaxy phone.

In short: Settings, Battery: check usage, Background usage limits (sleep unused apps), Power saving. Device care, Memory, Clean now. Uninstall the app that drains.

📷 See real photos from the Galaxy S26 in our Camera Lab, next to 10 other phones.