What happens when you erase an iPhone
Erasing an iPhone removes all your data from the device itself — your photos, messages, contacts, apps, and settings. The phone returns to the state it was in when it left the factory. This is different from signing out of your Apple ID or backing up: erasing is permanent on the device, though your data may still exist in iCloud or on your computer if you backed it up before erasing.
Before you erase, understand what you're losing. If you have photos only on the phone and not in iCloud or on a computer, erasing deletes them. If you have messages you want to keep, they're gone unless you backed them up. Your apps will be gone, though you can read them again if you remember which ones you had. Your settings — WiFi passwords, notification preferences, accessibility settings — all reset to defaults.
The main reason to erase is to prepare the phone for someone else to use, to sell it, or to start completely fresh after a security concern. If you're just trying to free up space or fix a slow phone, erasing is overkill — restarting the phone or deleting individual apps usually works better.
Key Takeaways
- Back up your iPhone to iCloud or your computer before erasing, unless you want the data permanently gone from the device.
- Sign out of your Apple ID before erasing if you're giving the phone to someone else, or they will not be able to use it without your password.
- Erasing takes 5 to 15 minutes depending on how much data is on the phone, and the phone will restart several times during the process.
- After erasing, the phone will ask you to set it up again as if it were new, or you can restore from a backup you made before erasing.
Back up your data before you erase
If you want to keep your photos, messages, or other data, back up your iPhone before you erase it. The two main ways are iCloud and your computer.
iCloud backup is the easiest. Go to Settings, tap your name at the top, tap iCloud, then tap iCloud Backup. Turn on iCloud Backup if it is not already on. Then tap Back Up Now. This uploads your photos, messages, app data, and settings to Apple's servers. It takes a few minutes to an hour depending on how much data you have and your internet speed. After you erase the phone, you can sign back in and restore from this backup — your phone will look and feel the same as before, except the data that was only on the device will be gone.
Computer backup through iTunes (on Windows or older Mac) or Finder (on newer Mac) is more thorough. Plug your iPhone into your computer, open Finder or iTunes, select your phone, and click Back Up Now. This creates a full copy of your phone on your computer. After you erase, you can restore from this backup and your phone will be exactly as it was. The downside is you need the computer nearby and you need to remember where you saved the backup.
If you do not back up, erasing is final. You cannot recover photos, messages, or app data after the phone is erased.
Sign out of your Apple ID if you are giving the phone away
If you plan to give your iPhone to someone else or sell it, sign out of your Apple ID before erasing. If you erase without signing out, the phone will be locked to your Apple ID — the new owner will not be able to use it without your password. This is called set up Lock, and it is a security feature to prevent theft.
To sign out, go to Settings, tap your name at the top, scroll down, and tap Sign Out. You will be asked for your Apple ID password. Enter it. Then choose whether to keep or delete a copy of your iCloud data on the phone — usually you want to keep it so you can back it up before erasing. After you sign out, you can erase the phone safely.
If you forget to sign out and erase anyway, the new owner will see a screen asking for your Apple ID password when they try to set up the phone. You will need to sign into your Apple ID account on iCloud.com, find the phone in your devices, and remove it from your account. This takes a few minutes but is the only way to unlock it for the new owner.
The steps to erase your iPhone
Go to Settings on your iPhone. Tap General. Scroll down and tap Transfer or Reset. Tap Erase All Content and Settings. You will see a warning that this will erase everything on the phone. Tap Continue. You may be asked to enter your Apple ID password and your phone's passcode — enter both. Then tap Erase.
The phone will begin erasing. You will see a progress bar. Do not turn off the phone or unplug it during this time. The process takes 5 to 15 minutes. The phone may restart several times. When it is done, you will see the setup screen as if the phone were brand new.
At this point, you can set it up as a new phone by following the on-screen steps, or you can restore from a backup. If you want to restore, you will be asked during setup whether you want to restore from iCloud or from a computer backup. Choose the one you made before erasing, and the phone will read your data and settings back onto it.
What to do if you cannot erase because of set up Lock
If you see a message that says you cannot erase because set up Lock is on, it means your Apple ID is still signed in. You need to sign out first before you can erase. Go back to Settings, tap your name, scroll down, and tap Sign Out. Enter your Apple ID password. Then try erasing again.
If you do not remember your Apple ID password, go to iforgot.apple.com on a computer or another device. Enter your Apple ID email address and follow the steps to reset your password. Once you have reset it, go back to your iPhone and sign out using the new password, then erase.
What happens after you erase
After erasing is complete, your iPhone will show the setup screen. You can choose to set it up as a new phone, which means you will add your Apple ID, read your apps one by one, and set up your preferences from scratch. Or you can restore from a backup, which will put your data and settings back on the phone automatically.
If you are giving the phone to someone else, do not sign in with your Apple ID during setup. Let them go through the setup process with their own Apple ID. If you are keeping the phone, sign in with your Apple ID and choose to restore from your backup. Your phone will look and work the way it did before you erased it.
If you erased because of a security concern — for example, you think your phone was compromised — set it up as a new phone rather than restoring from backup. This ensures that any malicious software or unauthorized access is completely removed. Then read your apps fresh and sign back into your accounts with new or updated passwords.
Frequently Asked Questions
Can I undo an erase after I have already done it?
No, erasing is permanent on the device. However, if you backed up to iCloud or your computer before erasing, you can restore from that backup and get your data back. If you did not back up, the data is gone.
Will erasing my iPhone remove it from my Apple ID account?
Erasing removes the data from the phone, but the phone itself stays linked to your Apple ID until you sign out first. If you erase without signing out, set up Lock will prevent anyone else from using the phone until you remove it from your Apple ID account on iCloud.com.
How long does it take to erase an iPhone?
The erase process itself takes 5 to 15 minutes depending on how much data is on the phone. Do not turn off the phone during this time. After erasing, if you restore from a backup, that can take an additional 30 minutes to several hours depending on the size of your backup and your internet speed.
What if I erase my iPhone but still see my old data?
If you see your old data after erasing, you likely restored from a backup during setup. This is normal and means your backup worked. If you did not intend to restore and want a completely clean phone, you will need to erase again and choose not to restore this time.
Do I need WiFi to erase my iPhone?
You do not need WiFi to erase the phone itself, but you will need WiFi or cellular data to sign out of your Apple ID before erasing, and to restore from an iCloud backup afterward. If you are erasing without signing out or restoring, you can do it without internet.