iPhone running slow? 8 fixes that speed it up

2 min read · 8 steps · Updated 2 October 2026

An iPhone that has become slow usually has a full disk, an old battery or an app working hard in the background. All three are easy to check.

Step by step

1. Restart the phone

   Hold the side button and a volume button, slide to power off, wait 30 seconds and turn it back on.

   Done

2. Free up storage

   A nearly full iPhone is a slow iPhone. See 7 ways to free up space.

   Done

3. Check battery health

   Open Settings, Battery, Battery Health. With a badly worn battery, iOS limits peak performance to prevent sudden shutdowns, and the page says so. A new battery restores full speed.

   Done

4. Turn off Low Power Mode

   A yellow battery icon means Low Power Mode is on, which reduces speed on purpose.

   Done

5. Update iOS and your apps

   Open Settings, General, Software Update, then update apps in the App Store.

   Done

6. Find a hungry app

   Open Settings, Battery and look at battery usage by app. An app high in the list that you barely use is working in the background. Delete it or turn off its Background App Refresh under Settings, General.

   Done

7. Let it cool down

   A hot iPhone slows itself to protect the electronics. Take it out of the sun and off the charger for a few minutes.

   Done

8. Wait a day after a big update

   After a major iOS update the phone re-indexes photos and files in the background. It is slower and warmer for up to a day or two, then recovers.

   Done

Good to know

Closing all your apps in the app switcher does not make the phone faster and can make it slower, because apps then have to start from scratch.

If the phone is five or more years old and the battery is healthy, newer apps may simply need more power than it has.

As a last resort, back up and erase the phone, then restore: how to factory reset an iPhone.

In short: Restart, free storage, check battery health, Low Power Mode off, update.