Replace your iPhone battery when it no longer holds a charge through a normal day, or when Apple's Battery Health tool shows capacity below 80 percent

Your iPhone battery degrades over time. Every full charge cycle — from 0 to 100 percent — wears the battery down a tiny bit. After 500 to 1,000 cycles, most iPhone batteries drop to 80 percent of their original capacity. At that point, you'll notice the phone dies faster, even if you're not using it differently.

You don't have to replace the battery the moment it hits 80 percent. That's just the point where Apple stops covering it under warranty. But if your phone is shutting down at 20 percent battery, or if you're charging it twice a day when you used to charge it once, that's a sign the battery is genuinely worn and a replacement will make the phone usable again.

Key Takeaways

  • Check your battery health in Settings > Battery > Battery Health & Charging — if it shows below 80 percent and your phone dies quickly, replacement is worth considering.
  • Apple charges between $69 and $99 to replace an iPhone battery, depending on the model, and the repair usually takes three to five business days.
  • Third-party repair shops often charge $30 to $60 less than Apple, but using non-Apple parts may void your warranty and could affect water resistance.
  • If your iPhone is more than five years old, the cost of battery replacement might be close to the cost of a used replacement phone, so compare prices before deciding.

How to check your battery health right now

Open Settings, then tap Battery, then Battery Health & Charging. You'll see a number labeled "Maximum Capacity" — that's the percentage of the battery's original charge your phone can now hold. You'll also see "Condition," which Apple rates as Normal, Degraded, or Service Recommended.

If the maximum capacity is above 85 percent and the condition says Normal, your battery is fine. You don't need to replace it yet. If it's between 80 and 85 percent and your phone still makes it through the day without dying unexpectedly, you can wait. If it's below 80 percent or the condition says Service Recommended, a replacement will noticeably improve how long your phone lasts.

What happens if you ignore a worn battery

A degraded battery doesn't suddenly stop working. Instead, your phone will shut itself down to protect the battery from damage. You might be at 30 percent charge and the phone powers off completely. You'll have to plug it in to turn it back on, even though the battery isn't actually empty. This is called unexpected shutdown, and it happens because the battery can't deliver the power the phone needs all at once.

Over time, unexpected shutdowns become more frequent. Your phone might die at 40 percent, then 50 percent. Eventually, the phone becomes unreliable — you can't trust it to stay on long enough to make a call or send a message. At that point, replacing the battery is the only fix that doesn't involve buying a new phone.

Apple battery replacement: cost and timeline

Apple replaces iPhone batteries at the Apple Store or through Apple's mail-in repair service. The cost depends on your model: older iPhones (iPhone 8 and earlier) cost $69, while newer models like the iPhone 15 cost $99. If your phone is still under warranty or covered by AppleCare+, the replacement is free.

In-store replacement usually takes the same day if you make an appointment and arrive early. Mail-in repair takes three to five business days, not counting shipping time. You'll need to back up your phone before you send it in, since Apple may erase it during the repair.

Third-party repair shops: faster and cheaper, with trade-offs

Independent repair shops like iFixit, Best Buy's Geek Squad, and local phone repair stores often charge $30 to $60 less than Apple. Many can replace the battery while you wait — sometimes in under an hour. If speed and cost matter more to you than warranty coverage, this is a real option.

The catch is that non-Apple batteries may not be identical to the original. Some third-party batteries are excellent and last just as long. Others degrade faster or don't hold as much charge. You also lose any remaining warranty coverage on the battery itself, and Apple won't service water damage that happens after a third-party repair, even if the damage is unrelated to the battery work.

Before you choose a third-party shop, ask whether they use OEM (original equipment manufacturer) batteries or aftermarket ones. OEM batteries are made to Apple's specs and are much more reliable. Also ask about their warranty on the battery — reputable shops offer at least 30 days.

When replacement doesn't make sense

If your iPhone is five or more years old, the cost of battery replacement might be close to the cost of a used iPhone in good condition. A used iPhone 11 or 12 costs $200 to $400, depending on storage and condition. If your battery replacement costs $99 and you're already thinking about upgrading, a used newer phone might be the better deal.

Also consider whether your phone has other problems. If the screen is cracked, the camera is broken, or the phone is running an old version of iOS that no longer receives security updates, battery replacement alone won't fix those issues. In that case, replacing the phone makes more sense than sinking money into repairs.

How to extend the life of your new battery

Once you replace the battery, you can slow down how fast it degrades again. Avoid letting the phone drop below 20 percent regularly — charge it when it hits 30 percent if you can. Don't leave it plugged in overnight; unplug it once it reaches 100 percent. Keep the phone cool; heat speeds up battery wear, so avoid leaving it in a hot car or direct sunlight.

In Settings > Battery > Battery Health & Charging, you can turn on "Optimized Battery Charging." This limits charging to 80 percent most of the time and only charges to 100 percent when you're likely to use the phone heavily. It's a small change, but it can add months to your battery's life.

Frequently Asked Questions

Can I replace the battery myself?

Technically yes, but it's difficult and risky. iPhones are glued together, and opening one without the right tools can crack the screen or damage the logic board. If you damage the phone during the repair, you've spent money on tools and parts and still have a broken phone. Unless you've done phone repairs before, it's safer and often cheaper to pay someone else.

Will a new battery make my old iPhone feel new again?

A new battery will fix unexpected shutdowns and make the phone last longer on a single charge. But it won't speed up the processor or improve the camera. If your phone feels slow, that's usually because the operating system has gotten heavier, not because the battery is worn. A new battery helps, but it's not a complete refresh.

How do I know if my battery is bad or if something else is draining it?

Check Battery Health first. If it says Normal and the capacity is above 85 percent, the battery itself is fine. The drain is probably a misbehaving app. Go to Settings > Battery and look at which apps used the most power in the last 24 hours. If one app is using far more than the others, try uninstalling it or restarting your phone.

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

Maximum Capacity is the percentage of the original charge your battery can hold — this is the number that matters most. Condition is Apple's judgment of whether the battery is Normal, Degraded, or needs Service. A battery at 82 percent capacity might still say Normal, while one at 79 percent might say Service Recommended. Both numbers together give you the full picture.