How to Securely Erase and Factory Reset Your Mac Before Selling

If you are planning to sell, trade-in, or give away your Apple computer, simply deleting your user account is not enough. To protect your privacy and ensure the new owner can actually use the device, you must know how to securely factory reset a Mac.

Failing to follow the correct procedure can leave your personal files recoverable or, worse, leave the computer permanently locked to your Apple ID due to Activation Lock.

Why You Must Reset Your Mac Properly

When you sign into a modern Mac, Apple links the hardware directly to your Apple ID. This is a brilliant anti-theft feature called Activation Lock. However, if you wipe the hard drive without first signing out, the next person to turn on the computer will be met with a password prompt they cannot bypass, turning your expensive hardware into a paperweight.

Here is the exact step-by-step workflow to prepare your Mac for a new owner safely.

Step 1: Back Up Your Data

Once you factory reset a Mac, your data is gone forever. Before doing anything else, connect an external hard drive and use Time Machine to create a complete backup.

1. Connect your external drive.
2. Open System Settings (or System Preferences on older versions).
3. Navigate to General > Time Machine.
4. Click Add Backup Disk, select your external drive, and wait for the backup to complete.

Step 2: Sign Out of iMessage and iCloud

This is the most critical step to disable Activation Lock and untether the hardware from your Apple ID.

Sign out of iMessage:

1. Open the Messages app.
2. In the top menu bar, click Messages > Settings.
3. Click the iMessage tab, then click Sign Out.

Sign out of iCloud:

1. Open System Settings.
2. Click your Apple ID name at the top of the sidebar.
3. Scroll to the very bottom and click Sign Out.
4. You will be asked if you want to keep a copy of your iCloud data on the Mac. Deselect all checkboxes, as you are erasing the machine anyway.

Step 3: Unpair Your Bluetooth Devices

If you are keeping your Bluetooth keyboard and mouse, but giving the Mac to someone else in the same house or office, you should unpair them. Otherwise, they might accidentally connect to the old Mac when the new owner turns it on.

1. Go to System Settings > Bluetooth.
2. Hover over the device you want to unpair and click the Info (i) button.
3. Click Forget This Device.

Step 4: Securely Factory Reset a Mac

The method you use to wipe the drive depends on the age of your Mac.

For macOS Monterey (and later) on Apple Silicon or T2 Intel Macs:

Apple introduced a highly secure, one-click reset option similar to the iPhone.

1. Open System Settings.
2. Navigate to General > Transfer or Reset.
3. Click Erase All Content and Settings.
4. Enter your administrator password. The Erase Assistant will show you exactly what is being deleted.
5. Click Continue and then Erase All Content & Settings. Your Mac will restart, securely destroy the cryptographic keys protecting your data, and boot to the standard “Hello” setup screen.

For Older Intel Macs (macOS Big Sur and earlier):

If you do not see the “Erase All Content and Settings” option, you must use macOS Recovery.

1. Restart your Mac and immediately press and hold Command (⌘) + R until you see an Apple logo.
2. Select Disk Utility and click Continue.
3. In the sidebar, select your primary volume (usually named Macintosh HD).
4. Click the Erase button in the toolbar.
5. Format it as APFS and click Erase Volume Group.
6. Once erased, quit Disk Utility and select Reinstall macOS from the main recovery menu.

When the installation finishes and the Mac restarts to the setup assistant, press Command (⌘) + Q to shut it down. Your Mac is now securely erased, reset, and ready for its new owner.