iOS updates usually take 30 minutes to two hours on your device, depending on your internet speed and which iPhone model you have
The time an iOS update takes to read and install breaks into two separate phases, and they happen at different speeds. The read itself — pulling the update file from Apple's servers to your phone — typically takes 15 to 45 minutes over Wi-Fi, longer on cellular. The installation phase, where your phone restarts and applies the changes, usually takes another 15 to 30 minutes. If your Wi-Fi is slow or unstable, the read can stretch to an hour or more.
Older iPhones (iPhone XS and earlier) tend to install updates more slowly than newer models because they have less processing power. A newer iPhone 15 might finish in 45 minutes total; an iPhone 11 might need 90 minutes. The first time you install a major iOS version on your device also takes longer than minor updates — sometimes significantly longer — because the system has more changes to explore.
Key Takeaways
- Plan for 30 minutes to two hours total, with read time depending heavily on your Wi-Fi speed and installation time depending on your iPhone model.
- Major iOS versions (like iOS 18.0) take longer than point releases (like iOS 18.1), sometimes by 30 minutes or more.
- Your phone will restart multiple times during installation and will be unusable during that period — do not force-restart or unplug power.
- Plugging into power before you start the update reduces the chance your phone will shut down mid-installation if the battery drains.
- Updates install faster on Wi-Fi than on cellular, and faster on 5 GHz Wi-Fi networks than 2.4 GHz ones.
Why read time varies so much between phones
The read speed depends almost entirely on your internet connection, not your phone. An iOS update file is typically 3 to 6 gigabytes for a major version. If your Wi-Fi connection runs at 50 megabits per second, that file takes about 8 to 10 minutes. If your connection is 10 megabits per second, it takes 40 to 50 minutes. Cellular networks are slower still — usually 5 to 20 megabits per second depending on signal strength and network congestion — so downloading over LTE or 5G can easily double the time.
The quality of your Wi-Fi router also matters. If your phone is far from the router or the signal is weak, the connection speed drops even if your internet plan is fast. Moving closer to the router or restarting it before you begin the update can cut read time noticeably. Pausing other downloads or streaming on your network while the update runs also helps, because the update will not compete for bandwidth.
Installation time depends on your iPhone's age and the update size
Once the file is downloaded, your phone restarts and begins installing. This phase is where your iPhone model matters most. Newer chips process the installation faster. An iPhone 15 with an A18 chip might complete installation in 15 minutes. An iPhone 11 with an A13 chip might need 30 to 40 minutes for the same update. Very old models like the iPhone 8 can take 45 minutes to an hour just for the installation phase.
Major version updates (iOS 17 to iOS 18, for example) also take longer than minor updates (iOS 18.0 to iOS 18.1). Major updates include bigger system changes, new security frameworks, and more files to rewrite. A major update might take 45 minutes to install; a minor update might take 15. If you are updating from a very old iOS version to a current one — say, from iOS 16 to iOS 18 — the installation can take significantly longer because the system has to explore years of changes.
What happens during installation and why you should not interrupt it
Your phone will restart several times during the installation process. The screen will show an Apple logo and a progress bar. During this time, your phone is completely unusable — you cannot make calls, send messages, or use apps. This is normal and expected. The restarts are part of the process, not a sign something went wrong.
Do not force-restart your phone, unplug it from power, or try to use it while the progress bar is running. Interrupting the installation can corrupt the system files and leave your phone in an unusable state. If the installation seems to be stuck on the progress bar for more than two hours, then you can consider force-restarting, but this should be a last resort. Plug your phone into power before you start the update so the battery does not drain and shut down the phone mid-installation.
How to make updates faster
Connect to Wi-Fi before starting the update — this is the single biggest factor you control. Use a Wi-Fi network that is fast and stable. If you have a choice between 5 GHz and 2.4 GHz on your router, connect to 5 GHz; it is faster, though it does not reach as far. Close other apps and pause any other downloads or streaming on your network.
Plug your phone into power and let the battery charge to 100 percent before you start. A full battery means the phone will not shut down if the installation takes longer than expected. Restart your phone before you begin the update — this clears temporary files and can speed up the process slightly. If you are updating from a very old iOS version, back up your phone first, then consider doing a factory reset and restoring from backup afterward; this can sometimes speed up the installation, though it is not necessary for most updates.
What to do if the update is taking much longer than expected
If the read is taking longer than three hours, your Wi-Fi connection is likely the problem. Check that you are still connected to Wi-Fi (sometimes phones drop the connection). Restart your router by unplugging it for 30 seconds and plugging it back in. Move closer to the router. If none of that helps, try connecting to a different Wi-Fi network — a neighbor's network, a coffee shop, or your phone's hotspot from a computer with a wired connection.
If the installation phase (the progress bar after restart) is taking longer than two hours, the phone may be stuck. Wait another 30 minutes to be sure — installation can be slow on older phones. If it is still stuck after that, force-restart your phone by pressing and releasing the volume up button, pressing and releasing the volume down button, then pressing and holding the side button until the Apple logo appears. This will interrupt the update, but it is better than leaving the phone in a broken state. You can try the update again after the restart.
Frequently Asked Questions
Can I use my phone while the update is installing?
No. Your phone will be completely unusable during the installation phase, which includes the progress bar and all the restarts. The read phase happens in the background while you use your phone normally, but once installation begins, you need to leave the phone alone until it finishes.
Will my phone turn off if the battery dies during an update?
Yes, and it can damage the system files. Always plug your phone into power before starting an update and let it charge to 100 percent. If the battery does drain and the phone shuts down mid-installation, plug it back in and restart it. The update will usually resume or restart from where it left off.
Why is my update taking three hours when everyone says 30 minutes?
Your Wi-Fi is likely slow or unstable. Check your internet speed using a speed test app. If it is below 10 megabits per second, the read will take much longer. Try restarting your router, moving closer to it, or connecting to a different network. Cellular downloads are also much slower than Wi-Fi.
Do I need to back up my phone before updating?
It is a good idea, though iOS updates rarely cause data loss. If something goes wrong during installation, a backup lets you restore your phone without losing photos, messages, or other data. Use iCloud backup or connect to a computer and use Finder (on Mac) or iTunes (on Windows).
Is it safe to update overnight and let it finish while I sleep?
Yes, as long as your phone is plugged into power. Set it on a table or desk where it will not overheat, and make sure Wi-Fi is on. The update will complete while you sleep, and your phone will be ready to use in the morning.