What to Do Before Selling Your Old Mac

The order matters here more than on most checklists, because erasing first strands you: once the Mac is wiped you can no longer sign out of the accounts still attached to it, and Activation Lock can leave the machine effectively unusable for whoever gets it next. Work down this list rather than jumping to the end.

1. Back up, even if you think you are done

Take a final Time Machine backup, or confirm the migration to your new Mac completed properly. People discover the one folder they forgot about a week after the old machine has gone.

2. Sign out of everything

1. iCloud. System Settings → your name → Sign Out. Whether you keep a local copy barely matters on a Mac you are about to erase.
2. Messages. Messages → Settings → iMessage → Sign Out.
3. Licensed apps. Anything with a seat limit — design tools, developer software, ours included — should be deauthorised here so the seat frees up for the new Mac.

3. Turn off Find My and unpair accessories

Find My leaves Activation Lock in place, and a locked Mac is close to worthless to a buyer. Signing out of iCloud handles it, but confirm rather than assume — see Find My on Mac. Then unpair any Bluetooth keyboard, mouse or trackpad you are keeping, or they will keep trying to reconnect to a machine that is no longer yours.

4. Erase properly

On Apple silicon and T2 Macs the correct route is System Settings → General → Transfer or Reset → Erase All Content and Settings. This is the same mechanism as an iPhone reset: it wipes your data cryptographically and returns the Mac to a clean setup screen, with no recovery mode or reinstall needed.

Do not bother with multi-pass secure erase utilities. On a modern Mac the internal drive is encrypted at the hardware level, so discarding the key is the erase. Extra passes achieve nothing except wear.

5. One last check before it goes

Boot it once after erasing. You should land on the Hello setup screen with no account details and no request for an Apple ID. If it does ask for your Apple ID to continue, Activation Lock is still active and you need to sign in and disable it before handing the Mac over. Selling a locked Mac is the most common and most avoidable mistake in this whole process.

Then set the replacement up properly — the migration guide and the setup checklist cover the rest.