How to Reset an iMac to Factory Settings

To reset an iMac to factory settings, back up anything you need, then use Erase All Content and Settings on an eligible iMac or erase the startup disk in macOS Recovery. The reset removes personal files and accounts, reinstalls or preserves macOS as appropriate, and returns the iMac to the setup screen.

What should you do before resetting an iMac?

Back up the iMac before erasing it. A factory reset permanently removes local documents, photos, downloads, apps, saved passwords, settings, and user accounts.

1. Save important files with Time Machine or copy them to trusted external storage. Confirm that several important files open from the backup.
2. Make sure any files stored only on the iMac have finished syncing to iCloud or another service.
3. Write down the Apple ID used on the iMac and make sure you know its password. You may need the password to turn off Find My or Activation Lock.
4. Sign out of iMessage. Open Messages, choose Messages, then Settings or Preferences, select iMessage, and choose Sign Out.
5. On an older iMac that will be given to someone else, sign out of iCloud from System Settings or System Preferences. Erase Assistant handles this automatically on supported systems.
6. Deauthorize the iMac in apps that limit the number of authorized computers, and sign out of any work, media, security, or licensed software accounts that require it.
7. Disconnect external drives and accessories that should not be erased. Keep the keyboard and mouse connected, and connect the iMac to reliable power and internet service.

How do you check which iMac reset method to use?

Choose About This Mac from the Apple menu to see the macOS version. The available reset method depends on both the software version and the iMac hardware.

• Erase Assistant: Use Erase All Content and Settings when it appears in macOS Monterey or later. This feature requires an iMac with Apple silicon or an Intel iMac with the Apple T2 Security Chip.
• macOS Recovery: Use Recovery Mode when Erase All Content and Settings is unavailable, including on many older Intel iMac computers.

Erase Assistant removes personal content while keeping the installed operating system ready for setup. Recovery Mode uses built-in recovery tools to erase the startup disk and reinstall macOS. Reinstalling macOS does not necessarily restore the exact version that originally shipped with the iMac.

How do you reset an iMac with Erase Assistant?

Erase Assistant is the simplest answer to “how do you reset an iMac to factory settings” when Erase All Content and Settings is available.

1. Open the Apple menu and choose System Settings.
2. Select General, then Transfer or Reset.
3. Select Erase All Content and Settings.
4. Enter the iMac administrator password when asked.
5. Review the summary of content that will be removed. If asked, provide the Apple ID password so Find My and Activation Lock can be disabled.
6. Confirm that you want to erase the iMac. The computer will restart and may briefly show a black screen or progress indicator.
7. Wait for the setup assistant to appear. Do not disconnect power during the erase.

In macOS Monterey, the command may be under the System Preferences menu rather than General: open System Preferences, then choose Erase All Content and Settings from the menu bar.

How do you reset an older iMac with macOS Recovery?

macOS Recovery is a set of startup tools used to repair a disk, erase an iMac, and reinstall macOS when Erase Assistant is unavailable.

1. Shut down the iMac.
2. For an Intel iMac, turn it on and immediately hold Command-R until an Apple logo or other startup screen appears. If the built-in recovery system does not load, Option-Command-R starts Internet Recovery and may install the latest compatible macOS.
3. If asked, select an administrator account and enter its password.
4. Choose Disk Utility from the recovery window, then select Continue.
5. Choose View, then Show All Devices. Select the internal startup volume, commonly named Macintosh HD.
6. Choose Erase. Use the format recommended by Disk Utility, commonly APFS for current macOS versions, and keep the suggested GUID partition scheme if that choice appears.
7. If an Erase Volume Group button appears, use it to remove the system and data volumes together. When erasing finishes, quit Disk Utility.
8. Select Reinstall macOS from the recovery window and follow the prompts. Choose the internal startup disk as the destination.
9. When the setup screen appears, complete setup or shut down the iMac if another person will set it up.

What happens to your Apple ID and data after an iMac reset?

An iMac reset erases local user accounts, personal files, installed apps, saved settings, and credentials from the internal startup disk. Data already stored in iCloud or retained in a separate backup is not deleted merely because the iMac is erased.

Erase Assistant signs out of Apple services, turns off Find My, and removes Activation Lock after the required Apple ID authentication. A manual Recovery Mode erase may not remove Activation Lock by itself, so sign out of iCloud and disable Find My before erasing an iMac that will change owners.

Files on disconnected external drives are preserved. Synced files may remain in their cloud accounts, but deleting files manually before signing out can also sync those deletions, which is why a verified backup should come first.

What should you do after resetting an iMac?

The Hello or setup assistant screen means the iMac is ready for initial setup. Select the language and region, connect to a network, and follow the prompts to create an account.

To restore your information, choose the option to transfer from a Mac or Time Machine backup during setup. If the iMac is being transferred to another person, do not create a new account; leave it at the setup screen and shut it down.

What should you do if the iMac reset will not start or gets stuck?

• Find My or Activation Lock blocks the reset: Connect to the internet and enter the Apple ID password associated with the iMac. If the account cannot be verified, recover access to the correct Apple ID before continuing.
• A firmware password appears: Enter the firmware password before using alternate startup options. If it is unknown, proof of ownership may be required to obtain help from Apple.
• Recovery will not load: On an Intel iMac, use a wired keyboard if startup keys are not detected, then retry Command-R or Option-Command-R immediately after powering on.
• macOS will not reinstall: Check the internet connection, verify that the correct internal disk was selected, and reopen Disk Utility to run First Aid before trying again.
• The process appears frozen: Keep the iMac connected to power and internet while a progress bar is moving. If the screen and progress remain completely unresponsive, restart into Recovery and repeat the disk check and installation.