Erase All Contents and Settings: prepare your Mac for disposal and more

If you have an Intel Mac with a T2 chip or one of the M1 series Macs, you’ll no doubt be aware of the introduction in Monterey of the new feature to Erase All Contents and Settings (EACAS). What you may not have realised yet is how powerful and useful this is.

I have, as you might have expected, several articles here about how to prepare a Mac to be passed on to someone else. In the most recent, I detail the following steps:

  1. disable Find My Mac and Activation Lock
  2. back up, migrate or copy files
  3. deauthorise that Mac for iTunes
  4. sign out of iCloud
  5. sign out of iMessage
  6. disable any firmware password
  7. reset NVRAM
  8. unpair Bluetooth devices
  9. erase the Mac and install macOS
  10. remove that Mac from your account in the Apple ID pane.

The penultimate step remains the most controversial, particularly when the internal storage is an SSD. You clearly don’t want to overwrite it all, rather to destroy its encryption keys by erasing its boot volume group, which then requires you to reinstall macOS and shut the Mac down when that reaches the personalisation stage.

These are fiddly and time-consuming processes, with a significant risk of error. The penalty for getting it wrong could also be serious, in handing that Mac’s next user your sensitive data.

EACAS makes this process far simpler:

  1. back up, migrate or copy files
  2. deauthorise that Mac for iTunes
  3. run EACAS
  4. remove that Mac from your account in the Apple ID pane.

You can start this process simply by opening System Preferences, where you’ll find the new command in the app menu. I’ve recently done this with my old M1 MacBook Pro 13-inch. Not only is it simple, quick and reliable, but the Mac’s new user will then receive your old Mac in factory condition, as new.


EACAS is more versatile too. There are other situations in which it’s now the preferred way to clean your Mac thoroughly. If you employ someone who uses a Mac, and they leave, this is the perfect way to prepare their Mac for their successor. You might also choose to use it on a Mac which you travel with, after visiting areas where your Mac could have unwanted software installed on it. For those who like to give their Mac a really ‘deep clean’, it’s as thorough as you need. And it’s a good alternative to some situations in which you might previously have put an M1 Mac into DFU mode and performed a full restore.

Its strength in many cases is that it leaves the System volume alone, so doesn’t require reinstalling macOS. As Big Sur and Monterey feature signed and sealed System volumes (SSV), you know that the System volume hasn’t been and can’t be tampered with, so it serves no purpose reinstalling that.

EACAS is a thoroughly practical tool, as well as an elegant demonstration of the benefits of the SSV and Secure Boot. It may not have looked like a major new feature in Monterey, but you’ll recognise it as one when you’ve used it.