Erasing a FileVault-encrypted T2-equipped Mac

Normally, reinstalling macOS on a Mac is a straightforward process:

1. Boot to macOS Recovery
2. Select Reinstall macOS from macOS Utilities.

3. Follow the onscreen instructions.

However, if you have a Mac equipped with a T2 chip where FileVault is turned on, there’s an extra step involved. When you boot to macOS Recovery on a T2 Mac with FileVault on, you will be prompted for the password of an account on the Mac which has admin privileges.

If you don’t have the password to any of the accounts which appear, you can select the Forget all passwords? option.

This will bring up a new screen where you can enter a FileVault Personal Recovery Key.

If you can provide either the account password or the personal recovery key, the next thing you should see is the macOS Utilities screen.

 

What if you don’t have either a password or a personal recovery key? Is your Mac now a paperweight? For more details, please see below the jump.

If you don’t have either an account password or recovery key available, you can erase the Mac’s boot drive without having to provide either. This way, the data stored in the encrypted drive can’t be touched but the Mac can still be rebuilt. To do this, please use the procedure shown below:

1. Boot to macOS Recovery
2. Click on the Recovery Assistant menu.

3. Select Erase Mac…

4. Select Erase Mac…

5. Click the Erase Mac button.

The Mac will erase the boot drive and reboot.

 

To reinstall the OS once the boot drive has been erased, use the procedure below:

1. Boot to macOS Recovery
2. Wait for the Mac to activate.

2. Select Reinstall macOS from macOS Utilities.

4. Follow the onscreen instructions.