Encrypt Time Machine Backups with Mac OS X

Time Machine backups can be encrypted right from your Mac. This means the backed up data is extremely safe from prying eyes and the very unlikely event of a cracking attempt, and it also means you’ll need a password to access the encrypted backups yourself.

Enabling encrypted backups in Time Machine for Mac OS X can be done in two ways, either during setup of Time Machine, or turned on at a later date if you decide you want to encrypt other backups. We’ll cover both.

How to Enable Encryption on New Time Machine Drives in Mac OS X

If you’re setting up a new Time Machine backup drive, enabling encryption is extremely easy:

• Connect the drive to the Mac, when asked to use the drive for Time Machine and going through the Time Machine setup, check the box for “Encrypt Backups”

You can also encrypt an existing Time Machine backup easily:

How to Encrypt Existing Time Machine Backups in Mac OS X

Already using Time Machine? Enabling encryption is just as simple. With the Time Machine drive connected to the Mac:

1. Open System Preferences from the  Apple menu and choose “Time Machine”
2. Choose “Options”, select the drive to protect, and choose “Encrypt backup disk” or “Encrypt Backups”

The wording varies slightly depending on which version of OS X you’re using.

You will need a modern version of OS X to have encryption as an available option to Time machine. This includes OS X El Capitan, OS X Yosemite, OS X Mavericks, OS X Mountain Lion, or newer to have the backup encryption option available, note the ability to encrypt existing drives only comes with newer versions of Mac OS X, though older versions of OS X will continue to have Time Machine backup support sans encryption.

Certain folders can be excluded from backups if they don’t need to be encrypted, but because they won’t be backed up you’ll need to handle backups of those files manually.

For those who don’t need to encrypt all backed up data, another excellent option is to encrypt folders with password-protected Disk Images. That disk image file can then be backed up as usual to a Time Machine drive, but only the data stored inside of it will be protected instead.