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

An iPhone battery degrades gradually over time. Apple designs them to retain 80 percent of their original capacity after 500 full charge cycles—roughly two to three years of daily use. After that point, you'll notice the phone drains faster, shuts down unexpectedly at low percentages, or struggles to run demanding apps.

The actual lifespan depends on how you charge, what you do with the phone, and the climate where you use it. A battery that gets one full cycle per day will last longer than one that gets two or three. Heavy use—gaming, video streaming, or constant location tracking—wears batteries faster than light browsing and texting.

Once a battery falls below 80 percent capacity, Apple's battery health feature will tell you so. You can check this in Settings > Battery > Battery Health & Charging. At that point, the phone still works, but you may want to replace the battery rather than buy a new phone.

Key Takeaways

  • A new iPhone battery typically lasts two to three years of daily use before dropping below 80 percent capacity.
  • One full charge cycle per day is the baseline; heavier use—gaming, video streaming, or constant location services—shortens battery life.
  • You can see your battery's current health percentage in Settings > Battery > Battery Health & Charging on any iPhone running iOS 16 or later.
  • Batteries degrade faster in hot climates and when charged to 100 percent regularly; keeping your phone cool and charging to 80 percent extends lifespan.
  • Once capacity drops below 80 percent, the phone still works but may shut down unexpectedly or drain quickly under load.

What counts as one charge cycle

A charge cycle is not the same as plugging in your phone. One cycle means you've used 100 percent of the battery's capacity—whether that happens in one day or spread across several days. If you use 50 percent of your battery one day and 50 percent the next, that's one cycle total.

This distinction matters because it means a phone you charge every other day will age slower than one you charge daily, even if both get the same total use. Someone who uses their iPhone heavily for four hours and then charges it has completed one cycle. Someone who uses it lightly for eight hours and then charges it has also completed one cycle, even though the second person used the phone longer.

Apple's 500-cycle estimate assumes you'll complete roughly one cycle per day. If you complete two cycles per day—draining the battery fully twice—you'll hit that 500-cycle limit in about 250 days instead of 500 days.

How heat and charging habits affect battery life

Lithium-ion batteries, which power iPhones, degrade faster when exposed to heat. Leaving your phone in a hot car, using it while charging, or living in a hot climate will shorten battery life noticeably. Apple recommends keeping iPhones between 50 and 95 degrees Fahrenheit for storage and use.

Your charging habits also matter. Charging to 100 percent every time and letting the battery drain to zero both cause extra stress. The battery ages fastest at the extremes. If you keep your phone between 20 and 80 percent charged most of the time, the battery will last longer than if you regularly charge to 100 percent or let it fully drain.

Modern iPhones include Optimized Battery Charging, a feature that learns your charging patterns and slows charging to 80 percent overnight, then tops up to 100 percent before you wake up. This reduces the time the battery spends at full charge. You can enable it in Settings > Battery > Battery Health & Charging > Optimized Battery Charging.

Signs your battery needs replacement

The most obvious sign is the battery health percentage dropping below 80 percent. At that point, Apple considers the battery degraded enough to warrant replacement. You'll see this in Settings > Battery > Battery Health & Charging.

Before you check the percentage, you might notice the phone behaving differently. The battery drains noticeably faster during normal use. Apps that used to run smoothly now cause the phone to slow down or stutter. The phone shuts down suddenly at 20 or 30 percent battery, even though it used to run until 5 percent. These are all signs the battery can no longer deliver the power the phone demands.

Some users see a yellow battery icon in the status bar, which indicates the phone is in Low Power Mode. This is not a sign of battery degradation—it's just a mode you can turn on or off. The real indicator is the health percentage or the unexpected shutdowns.

Replacing an iPhone battery versus buying a new phone

Apple offers battery replacement at its stores and authorized service providers. The cost varies by model—typically between $50 and $100 for most iPhones. The process takes one to two hours if you go in without an appointment, or you can schedule ahead to avoid waiting.

If your phone is still fast enough for your needs and the screen and body are in good shape, battery replacement is usually cheaper than upgrading to a new phone. A new battery can extend the phone's useful life by another two to three years. If the phone is also slow, the screen is cracked, or you want new features, buying a new phone might make more sense.

Third-party repair shops also offer battery replacement, often for less money than Apple. The trade-off is that non-Apple batteries may not last as long, and you lose any remaining warranty coverage. Some third-party shops do quality work; others use low-grade batteries that fail quickly.

How to extend your battery's lifespan right now

Turn on Optimized Battery Charging in Settings > Battery > Battery Health & Charging. This is the single most effective setting for slowing degradation. It prevents the battery from spending hours at 100 percent charge.

Keep your phone out of heat. Don't leave it in direct sunlight, in a hot car, or on a windowsill on warm days. If the phone gets hot during use, close apps and let it cool down before charging.

Charge more often but to lower percentages. Instead of waiting until the battery is at 20 percent to charge, plug in at 30 or 40 percent. Instead of charging all the way to 100 percent, unplug at 80 percent if you're not about to leave the house. These small changes add up over months.

Enable Low Power Mode when the battery drops below 30 percent. This reduces background activity and slows drain. You can also turn it on manually in Settings > Battery > Low Power Mode, even when the battery is full.

Battery life versus battery health: what's the difference

Battery health is the percentage you see in Settings—how much capacity the battery has lost compared to when it was new. A battery at 80 percent health still holds 80 percent of its original charge.

Battery life is how long the phone runs on a single charge. This depends on battery health, but also on what you're doing. A phone with 85 percent battery health might run for 12 hours of light use but only 6 hours of heavy gaming. The same phone at 70 percent health might run 10 hours of light use and 5 hours of gaming.

You can see estimated battery life in Settings > Battery > Battery Health & Charging. It shows how many hours of typical use you can expect before the phone needs charging. This number drops as the battery ages, but it also changes day to day based on what apps you've been using.

Frequently Asked Questions

Can I check my battery health on an older iPhone?

Battery Health & Charging is available on iPhone 6 and later running iOS 16 or newer. If you have an older iPhone or older iOS version, you won't see the percentage, but you can still notice when the battery is degrading by how fast it drains and whether it shuts down unexpectedly.

Does using my iPhone while charging damage the battery?

Using the phone while charging generates heat, which speeds up degradation. It's better to let the phone charge without heavy use. Light use—texting or browsing—while charging is fine, but avoid gaming or video streaming during charging.

Will my battery last longer if I turn off background app refresh?

Turning off background app refresh reduces daily drain, so the battery lasts longer per charge. However, it doesn't slow the rate at which the battery degrades over time. The battery will still hit 80 percent capacity at roughly the same point—you'll just get more use out of each charge in the meantime.

Is it bad to leave my iPhone plugged in overnight?

Modern iPhones with Optimized Battery Charging handle overnight charging well. The phone charges to 80 percent quickly, then waits until shortly before you wake up to finish charging to 100 percent. This reduces the time the battery spends at full charge. If you turn off Optimized Battery Charging, leaving it plugged in all night does cause extra wear.

What temperature is too hot for an iPhone battery?

Apple recommends keeping iPhones below 95 degrees Fahrenheit during use. Anything above that starts to degrade the battery faster. In very hot climates, try to keep the phone in shade, avoid using it in direct sunlight, and don't leave it in cars or enclosed spaces where it can heat up.