The most common culprits: background activity, screen brightness, and location services
Your iPhone battery drains fastest when apps run in the background, your screen stays at full brightness, or location services stay on for apps that don't need them. These three things account for most battery loss on a working phone. A phone that loses 20 percent of its charge in an hour is usually running one app constantly in the background, keeping the screen at maximum brightness, or both.
The second-most common cause is an old battery. iPhones shipped before 2020 often lose the ability to hold a full charge after two or three years of daily use. If your phone is older than three years and drains from 100 to 0 percent in less than eight hours of normal use, the battery itself may be worn out rather than your settings or apps.
Key Takeaways
- Check Settings > Battery to see which apps used the most power in the last 24 hours or 10 days — the app at the top is usually the problem.
- Turn off background app refresh for apps you don't need running when you're not using them, especially email, maps, and social media.
- Lower your screen brightness or turn on Auto-Brightness so your display uses less power throughout the day.
- Turn off location services entirely or set individual apps to "While Using" instead of "Always" so they only track you when you open them.
- If your phone is three years old or older and drains in under eight hours of normal use, the battery itself may be degraded and worth replacing.
How to find which app is draining your battery
Open Settings, tap Battery, then tap Battery Usage. You will see a list of apps ranked by how much power they used in the last 24 hours. The app at the top used the most. Swipe left on the screen to see the last 10 days instead, which shows you patterns — if the same app is always at the top, that app is your problem.
Below each app name, you will see a percentage. An app using more than 10 percent of your total battery in 24 hours is heavy. An app using more than 20 percent is very heavy. If the top app is one you barely use, tap it to see whether it ran in the background or only when you had it open. The detail view tells you the split.
Some apps will show "Background Activity" underneath the name. That means the app was running even when you weren't using it. That is the main reason to turn off background app refresh for that app.
Turn off background app refresh for specific apps
Open Settings, tap General, then tap Background App Refresh. You will see a list of every app on your phone. Toggle off the switch next to any app you don't need running in the background. Email, Maps, social media apps, and news apps are the safest to turn off because you can open them manually whenever you want to check them.
You can also turn off background app refresh entirely by toggling the switch at the top of the list, but that will stop all apps from refreshing. Most people prefer to leave it on and turn it off only for the apps that drain the most power.
After you turn off background app refresh for an app, that app will no longer check for new messages, location updates, or other data unless you open it yourself. You will not get notifications from that app unless it is open.
Lower your screen brightness and turn on Auto-Brightness
Your screen is often the single biggest power drain on your phone. Open Settings, tap Display & Brightness, and drag the brightness slider all the way down to the left. Your screen will be dimmer, but you can still read it in most indoor lighting.
Turn on Auto-Brightness by toggling the switch at the bottom of the Display & Brightness screen. Auto-Brightness adjusts your screen brightness based on the light around you, so it stays dim indoors and gets brighter in sunlight without you having to change it manually. This usually saves 10 to 15 percent of your daily battery use.
If you use your phone mostly indoors, keeping brightness at 30 to 40 percent is usually enough. If you spend time outside, Auto-Brightness will handle the adjustment for you.
Turn off location services or limit them to "While Using"
Open Settings, tap Privacy & Security, then tap Location Services. Toggle off Location Services entirely if you don't use maps or location-based reminders. If you do use those features, keep Location Services on but scroll down to see individual apps.
For each app, tap it and choose "While Using" instead of "Always". "While Using" means the app can see your location only when you have it open. "Always" means the app can track you in the background even when you are not using it. Maps, weather, and fitness apps often ask for "Always" permission, but they work fine with "While Using".
Apps that track your location constantly in the background can drain 5 to 10 percent of your battery per day. Switching them to "While Using" is one of the fastest ways to extend your battery life.
Check whether your battery itself is degraded
Open Settings, tap Battery, then tap Battery Health & Charging. Look at the number next to "Maximum Capacity". This number tells you what percentage of the battery's original charge it can still hold. A new iPhone shows 100 percent. A battery at 80 percent can hold 80 percent of the charge it could when new.
If your phone is three years old or older and the maximum capacity is below 80 percent, your battery is degraded. A phone with a 60 percent capacity battery will drain much faster than a phone with a new battery, no matter what apps you have or what settings you use. In that case, replacing the battery is usually the fastest fix.
Apple and most phone repair shops can replace an iPhone battery. The cost varies by model, but usually runs between $50 and $100. A new battery will restore your phone's battery life to what it was when you first bought it.
Other settings that drain battery
Bluetooth, Wi-Fi, and mobile data all use power, but usually not as much as apps or screen brightness. You can turn off Bluetooth and Wi-Fi when you are not using them by opening Control Center and tapping the icons. Turning off Wi-Fi and Bluetooth saves a small amount of power, but the difference is usually less than 5 percent per day.
Push notifications also drain battery because your phone has to check for new messages constantly. If you get dozens of notifications per day, turning off notifications for apps you don't need to hear from when ready can help. Open Settings, tap Notifications, and toggle off Allow Notifications for apps you don't need to alert you.
Vibration uses slightly more power than sound, so turning off vibration for notifications and calls saves a tiny amount of battery. The savings are usually too small to notice unless you get hundreds of notifications per day.
Frequently Asked Questions
Why does my iPhone battery drain faster in cold weather?
Cold temperatures slow down the chemical reactions inside your battery, so it cannot deliver power as quickly. Your phone may shut down at 20 percent battery in freezing weather even though the battery is not actually empty. Warm your phone up indoors and the battery will work normally again. This is temporary and does not mean your battery is damaged.
Does closing apps in the background save battery?
No. Closing apps by swiping them away in the app switcher does not save battery because those apps are not running. Your phone only runs apps you have open or apps you have given permission to run in the background. Closing apps actually uses more battery because your phone has to reload them from storage the next time you open them.
Will turning on Low Power Mode really extend my battery?
Yes. Low Power Mode reduces screen brightness, limits background app refresh, and slows down your processor. It usually extends your battery life by 15 to 25 percent. You can turn it on in Settings > Battery, or swipe up from the bottom of your screen and tap the battery icon in Control Center.
Can a software update fix battery drain?
Sometimes. Apple releases updates that fix bugs causing apps to use too much power. If your battery drain started after a recent update, installing the latest iOS version may help. Go to Settings > General > Software Update to check for new versions.
Is it bad to charge my iPhone every night?
Modern iPhones are designed to charge overnight without damage. Your phone stops charging at 100 percent and stays there, so leaving it plugged in all night does not wear out the battery faster. However, keeping your phone plugged in constantly at 100 percent for months or years can slightly reduce battery lifespan over time.