A new iPhone battery lasts two to three years under normal use

An iPhone battery degrades over time because it can only charge and discharge a limited number of times before its capacity shrinks. Apple designs iPhone batteries to retain 80 percent of their original capacity after 500 full charge cycles. Most people hit that point in about two to three years of daily use. After that, your phone still works, but the battery drains faster and you'll need to charge more often.

How quickly your battery wears out depends on how you use your phone. Heavy users who charge multiple times a day, leave their phone in hot environments, or run demanding apps constantly will see capacity drop faster. Someone who charges once a day in normal conditions will stretch that two to three years closer to the upper end.

You can check your battery's current health in Settings. Go to Settings > Battery > Battery Health & Charging. The number shown there—usually between 80 and 100 percent for a newer phone—tells you what percentage of the original capacity remains. Once it drops below 80 percent, Apple considers the battery degraded, though your phone will still function.

Key Takeaways

  • A new iPhone battery typically lasts two to three years before capacity drops below 80 percent under normal daily use.
  • You can see your battery's current health percentage in Settings > Battery > Battery Health & Charging on any iPhone running iOS 16 or later.
  • Hot environments, frequent charging, and heavy app use all speed up battery degradation beyond the normal timeline.
  • When battery health falls below 80 percent, you'll notice the phone drains faster, but it will continue to work until capacity drops much lower.

What happens as your battery ages

As an iPhone battery completes charge cycles, the chemical compounds inside gradually lose their ability to hold a charge. This is not a defect—it's how lithium-ion batteries work. After 500 cycles, Apple's testing shows the battery retains about 80 percent capacity. After 1,000 cycles, it typically holds around 60 to 70 percent.

You'll notice the effects before the numbers get that low. Around the 80 percent mark, your phone might drain from full to empty noticeably faster than it did when new. You may also see the battery percentage jump suddenly—from 20 percent to 5 percent, for example—because the battery can no longer accurately report its charge level. Some users also experience unexpected shutdowns when the battery is under heavy load, even if the percentage shown is not that low.

Apple added a feature called battery health management (available in iOS 13 and later) that slows degradation by limiting how much the battery charges. If you turn this on in Settings > Battery > Battery Health & Charging, your phone will not charge past 80 percent during normal use. This extends the battery's lifespan, though it means your phone's maximum runtime shrinks slightly.

Factors that speed up battery wear

Temperature is the single biggest factor. Lithium-ion batteries degrade much faster in heat. If you regularly use your iPhone in direct sunlight, in a hot car, or while running intensive apps like games or video editing, the battery will age faster than the two to three year baseline. Even storing a phone in a warm place when you're not using it accelerates degradation. Cold temperatures slow degradation temporarily, but extreme cold can also damage the battery.

Charging habits matter too. Charging to 100 percent and letting the battery drain to 0 percent repeatedly wears it out faster than keeping it between 20 and 80 percent. If you charge your phone multiple times a day, you're completing more charge cycles per year than someone who charges once daily, so the battery will degrade sooner. Fast charging generates heat, which also speeds up wear, though modern iPhones manage this with built-in thermal controls.

Background activity and demanding apps drain the battery more deeply and more often, which means more charge cycles. If your phone is constantly syncing data, running location services, or pushing notifications, the battery works harder and wears out faster than it would with lighter use.

When to replace your iPhone battery

You don't have to replace the battery the moment it drops below 80 percent. Many people continue using their phones at 70 or even 60 percent capacity without major problems. The decision depends on whether the degradation affects your daily life. If you're charging twice a day and still running out of power, or if your phone shuts down unexpectedly, replacement becomes practical.

Apple offers battery replacement through its stores and authorized service providers. The cost varies by iPhone model and your location, but typically ranges from $50 to $100 for most current models. If your phone is still under warranty or covered by AppleCare+, the replacement may be covered at no cost. You can check your coverage status in Settings > General > About, then tap Service & Support.

Third-party repair shops also offer battery replacement, often at lower cost than Apple. However, using a non-Apple battery or a non-certified technician may affect your warranty and could result in a lower-quality replacement. If you choose a third-party route, confirm they use genuine or certified batteries and ask about their warranty on the replacement.

How to extend your battery's lifespan

Keep your phone cool. Avoid leaving it in direct sunlight, in a car on a hot day, or in other warm environments. If your phone gets hot during use, close demanding apps and let it cool down. Use a case that doesn't trap heat, and avoid using your phone while it's charging if possible.

Charge more frequently but to lower levels. Instead of charging from 0 to 100 percent once a day, charge from 20 to 80 percent twice a day if you can. This reduces the stress on each charge cycle. If you have battery health management turned on (Settings > Battery > Battery Health & Charging), your phone will automatically stop charging at 80 percent during most of the day, which helps extend battery life.

Reduce background activity. Turn off location services for apps that don't need it, disable background app refresh for apps you don't use constantly, and turn off push notifications for non-essential apps. These steps reduce how hard the battery works and how often it cycles.

Use low-power mode when your battery is below 20 percent, or even earlier if you know you won't be near a charger soon. Low-power mode reduces performance and background activity, which slows battery drain and gives the battery a lighter workload.

Signs your battery needs replacement soon

Rapid drain is the most obvious sign. If your phone goes from 50 percent to dead in an hour of normal use, the battery is significantly degraded. Another common sign is unexpected shutdowns—your phone powers off even though the battery percentage shows 20 or 30 percent. This happens because the battery can no longer deliver the power the phone needs under load.

Swelling is a rare but serious sign. If your iPhone feels thicker than normal, the back is bulging, or the screen is separating from the body, the battery may be swelling. Stop using the phone when ready and take it to Apple or a certified repair shop. A swollen battery can damage other components or pose a safety risk.

Slow performance can also indicate battery problems. iOS automatically reduces processor speed on phones with degraded batteries to prevent unexpected shutdowns. If your phone feels noticeably slower than it used to, check your battery health. If it's below 50 percent, replacement will likely restore normal speed.

Frequently Asked Questions

How do I know if my battery is still good?

Open Settings > Battery > Battery Health & Charging and look at the maximum capacity percentage. Above 80 percent means the battery is in good condition. Between 70 and 80 percent is acceptable for most users. Below 70 percent, you'll likely notice faster drain and may want to consider replacement.

Can I replace just the battery, or do I have to replace the whole phone?

You can replace just the battery. Apple and certified repair shops can swap out the battery while keeping your phone. The process takes a few hours to a few days depending on where you go. Third-party repair shops are often faster and cheaper, but confirm they use quality batteries.

Does turning off my phone when I'm not using it help the battery last longer?

Turning off your phone slows battery drain while it's off, but it doesn't significantly extend the lifespan of the battery itself. Battery degradation happens during charge cycles, not from sitting powered on. If you want to extend battery life, focus on keeping it cool and avoiding full discharge cycles.

Is it bad to leave my iPhone charging overnight?

Modern iPhones have safeguards that stop charging at 100 percent and trickle-charge to maintain that level, so overnight charging won't damage the battery. However, if your phone gets hot while charging, unplug it and let it cool. Heat is the main enemy of battery lifespan, so avoid charging in warm environments.

What's the difference between battery health and battery capacity?

Battery health is the percentage shown in Settings—it tells you what portion of the original capacity remains. Battery capacity is the total amount of energy the battery can hold, measured in milliamp-hours (mAh). If health is 80 percent and the original capacity was 3,000 mAh, the current capacity is about 2,400 mAh.