How to Factory Reset a Mac Before Selling

Complete guide to factory reset your Mac safely before selling. Includes backing up data, signing out of accounts, and erasing the drive securely.

1. Back up your important data. Connect an external drive and open Time Machine from System Preferences. Click 'Back Up Now' to create a complete backup. Alternatively, manually copy important files to cloud storage or an external drive.
2. Sign out of all Apple services. Open System Preferences and click Apple ID. Click 'Overview' then 'Sign Out'. Open iTunes and choose Account > Authorizations > Deauthorize This Computer. Sign out of iMessage by opening Messages > Preferences > iMessage and clicking 'Sign Out'.
3. Unpair Bluetooth devices. Open System Preferences > Bluetooth. Click the 'X' next to each paired device to remove it. This prevents the new owner from accessing your devices and ensures your devices won't automatically connect.
4. Restart into Recovery Mode. Restart your Mac and immediately hold Command + R until the Apple logo appears. On Apple Silicon Macs, hold the power button until 'Loading startup options' appears, then click Options and Continue.
5. Erase the startup disk. In Recovery Mode, open Disk Utility from the macOS Utilities window. Select your startup disk (usually named 'Macintosh HD') from the sidebar. Click 'Erase' and choose 'Mac OS Extended (Journaled)' or 'APFS' format depending on your macOS version.
6. Reinstall macOS. Close Disk Utility and select 'Reinstall macOS' from the macOS Utilities window. Follow the on-screen instructions to download and install a fresh copy of macOS. This process takes 30-60 minutes depending on your internet connection.
7. Complete initial setup partially. When macOS installation finishes, proceed through the setup assistant until you reach the user account creation screen. Press Command + Q to quit the setup assistant instead of creating an account. This leaves the Mac ready for the new owner to set up their own account.