macOS: Encrypt USB Storage

Modified on Thu, 6 Oct, 2022 at 9:35 AM

If you need to encrypt your external USB storage media (for general security, or compliance with a framework like Cyber Essentials) and use a Mac with macOS Mojave or newer, you can encrypt the disk without any additional tools. Finder has this capability built-in.

Encrypting a device using Finder applies encryption using the same security level (XTA-AES) as FileVault 2 applies to your operating system drive, so it's very secure indeed. 


  • A Mac
  • macOS Mojave (10.14) or newer (Cataline, Big Sur, Monterey, Ventura)
  • A USB storage device


  • The USB storage device must be formatted using the macOS Disk Utility to use GUID partition mapping. If you're not sure how to do this, or have no idea what it means at all, just give one of our friendly engineers a call!
  • If the password used to unlock the disk is lost or mislaid, all data on the disk will be lost.


  • Connect the USB storage media to your Mac
  • Launch Finder
  • Find your USB storage media in the left hand navigation menu
  • Control-click on the storage media
  • Click Encrypt (your storage device name) from the dropdown menu
  • Enter a strong password in the prompts (see our guidance on creating strong passwords, or create one using a password manager)
  • Click Encrypt Disk

Was this article helpful?

That’s Great!

Thank you for your feedback

Sorry! We couldn't be helpful

Thank you for your feedback

Let us know how can we improve this article!

Select at least one of the reasons
CAPTCHA verification is required.

Feedback sent

We appreciate your effort and will try to fix the article