The most common reasons your iPhone battery empties quickly

Fast battery drain usually comes from one of three sources: an app running constantly in the background, a setting that keeps your screen or radios active when you don't need them, or a battery that has straightforward worn out from age. Most of the time it is the first two, and you can fix them yourself in minutes. A battery that has lost capacity is the one thing you cannot fix at home—that requires a replacement.

The fastest way to find out which one is happening is to check your battery usage report. Open Settings, tap Battery, then Battery Health & Charging. Look at the number next to Maximum Capacity. If it is still above 80 percent, your battery is probably fine and something else is draining it. If it has dropped below 80 percent, your battery has degraded and a replacement will help, though you should still check the other causes first.

Key Takeaways

  • Check your battery's maximum capacity in Settings > Battery > Battery Health & Charging; if it is below 80 percent, the battery itself has worn out and a replacement will help.
  • Background app refresh, location services, and screen brightness drain battery fastest, and you can turn them off for individual apps without losing core phone function.
  • Open Settings > Battery > Battery Usage to see which apps are consuming the most power in the last 24 hours or 10 days.
  • Turning off Bluetooth, Wi-Fi, and cellular when you are not using them saves significant battery, though location services drains more power than any of these.
  • If your battery maximum capacity is above 80 percent and you have turned off the biggest power drains, the problem is usually a single app misbehaving.

How to read your battery usage report

Your iPhone tracks which apps consumed power over the last 24 hours and the last 10 days. Open Settings, tap Battery, then Battery Usage. You will see a list of apps ranked by how much battery they used. The percentages add up to 100 percent of the battery your phone consumed in that time period.

Look for apps that are using much more than you would expect. If you checked email once but Mail is showing 15 percent battery use, something is wrong with that app. If Maps is at 8 percent but you only used it for directions once, it may still be running location services in the background. Tap any app name to see whether it was active on your screen or running in the background—this tells you whether the app itself is the problem or whether a setting is letting it run when you are not using it.

An app that uses 5 to 10 percent of your battery in a day is normal if you use it regularly. An app that uses 20 percent or more, or one that shows high background usage when you barely use it, is the culprit.

Turn off background app refresh for power-hungry apps

Background app refresh lets apps check for new information even when you are not looking at them. Mail can fetch new messages, Maps can update location, and social media apps can refresh feeds. This is useful, but it drains battery constantly. You do not have to turn it off entirely—you can disable it for individual apps.

Open Settings, tap General, then Background App Refresh. You will see a list of every app that has permission to run in the background. Toggle off the ones you do not need to update constantly. Keep it on for Mail, Messages, and any app you rely on for notifications. Turn it off for games, social media, news apps, and anything else that can wait until you open it.

This single change often cuts battery drain by 10 to 20 percent because it stops apps from waking your phone and using the radio to fetch data all day long.

Disable location services for apps that do not need it

Location services is one of the biggest battery drains on any phone because it keeps your GPS radio active and constantly calculating your position. Many apps ask for location permission but do not actually need it to work. A weather app needs your location once to show your local forecast. A notes app does not need it at all.

Open Settings, tap Privacy & Security, then Location Services. You will see every app that has asked for location permission. Tap each one and choose Never for apps that do not need to know where you are. For apps that do need location—Maps, weather, fitness apps—choose While Using instead of Always. This lets them use your location when you are actively using the app, but stops them from tracking you in the background.

If you use location-based reminders or Find My iPhone, you will need to keep location services on for some apps. But for most apps, turning it off saves significant battery without breaking any feature you actually use.

Lower screen brightness and turn on auto-brightness

Your screen is the second-biggest battery drain after location services. A bright screen uses far more power than a dim one. Open Settings, tap Display & Brightness, and drag the brightness slider down to a level that is comfortable for you. You do not have to go all the way to minimum—even dropping from maximum to 50 percent saves noticeable battery.

Turn on Auto-Brightness so your phone adjusts the screen brightness based on the light around you. In a dark room, your screen will dim automatically. In bright sunlight, it will brighten. This prevents you from running a bright screen in a dark room, which wastes battery for no reason.

If you spend a lot of time on your phone, lowering brightness is one of the easiest ways to extend battery life without changing how you use your phone.

Turn off Bluetooth and Wi-Fi when you are not using them

Bluetooth and Wi-Fi radios use power even when they are not connected to anything, because they are constantly scanning for devices and networks. If you are not using wireless headphones or a smartwatch, turn off Bluetooth. If you are on cellular data, turn off Wi-Fi. You can toggle both from Control Center—swipe down from the top right corner of your screen.

This is a smaller drain than location services or background app refresh, but it adds up. Turning off both can save 5 to 10 percent of your battery in a day if you are not actively using them.

You do not have to leave them off all the time. Turn them back on when you need them. The point is to stop them from running when you are not getting any benefit from them.

When to replace your iPhone battery

If your battery maximum capacity has dropped below 80 percent, your battery has degraded and will not hold a charge as long as it used to. Apple and most phone repair shops can replace the battery. The cost varies, but Apple typically charges between $50 and $70 for an out-of-warranty battery replacement, depending on your iPhone model. Some third-party repair shops charge less.

Before you replace the battery, make sure you have turned off the settings and apps that drain power fastest. A new battery will not help if background app refresh and location services are still running constantly. But if you have done all of that and your battery still empties in a few hours, a replacement is the answer.

You can also check whether your iPhone is in Low Power Mode, which limits performance to save battery. Open Settings, tap Battery, then Low Power Mode. If it is on, your phone is already trying to stretch battery life. Turn it off to see whether your phone feels faster, then decide whether the battery life trade-off is worth it to you.

Frequently Asked Questions

Can I replace my iPhone battery myself?

iPhones are sealed devices and opening one requires special tools and knowledge. Attempting it yourself risks damaging the screen, battery, or internal components. Apple and authorized repair shops have the right equipment and can do it safely. Some third-party repair shops also offer battery replacement, though quality varies.

Does closing apps in the app switcher save battery?

No. Closing apps by swiping them away from the app switcher does not save battery because iOS automatically suspends apps you are not using anyway. The only thing that saves battery is turning off background app refresh and location services, which prevent apps from running when you are not looking at them.

Will turning on Low Power Mode hurt my phone?

No. Low Power Mode reduces performance slightly and disables some features like background app refresh, but it does not damage your phone. You can turn it on and off whenever you want. Many people leave it on all the time to extend battery life, even if their battery is not low.

Why does my battery drain faster in cold weather?

Lithium batteries, which power iPhones, work less efficiently when they are cold. Your battery may show a lower percentage than it actually holds, and your phone may shut down even though the battery is not truly empty. Warm your phone up indoors and the battery percentage will usually return to normal. This is temporary and does not mean your battery is damaged.

Is it bad to charge my iPhone overnight?

Modern iPhones have built-in protections that stop charging once the battery reaches 100 percent, so leaving your phone plugged in overnight will not damage the battery. However, keeping a battery at 100 percent constantly for long periods can slightly speed up degradation over years. If you want to extend battery lifespan, you can use Optimized Battery Charging in Settings > Battery > Battery Health & Charging, which limits charging to 80 percent most of the time.