If your USB drive contains sensitive information that you don't want to fall into the wrong hands, it makes sense to enable a password – the total process only takes a couple of minutes.

By default, your USB drive is very likely password-free, which means anybody with the stick can plug it into their own computer and browse your files. If you store financial information or security details on your USB drive, that could lead to an even bigger problem.

Below, we have step-by-step instructions for both Windows and Mac users. Plus, you'll spot tips on how to create a secure password if you're stuck for ideas.

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Question of the month: What's the best way to secure the files on my USB stick?

'I have sensitive financial files that I store on a USB stick. I’m worried that if I lose the stick someone could access all of my files. Can I add a password?'

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Creating a password for your USB stick

On Windows 10 and 11 Pro

To secure your external drive on Windows you can use BitLocker, which is an encryption program included with Microsoft's operating system. If you have a Home edition of Windows, you need to use VeraCrypt instead (see further down this page).

Head to the Control panel, change your view to Large icons (this will improve your view) and follow these steps:

1. Select Bitlocker drive encryption and you'll see all of the drives connected to your device.
2. Click on the USB drive you wish to encrypt and select Turn on Bitlocker.
3. In the Window that opens, select Use a password to unlock the drive and enter a strong and unique password.
4. On the next page, you'll be presented with details on managing your recovery key. You can save it to your Microsoft account, print it or save it to a file.
5. Select Encrypt entire drive and choose Compatible mode.
6. Finally, choose Start Encrypting.

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On macOS

If you're looking to password-protect an external drive on Mac, note that it needs to be formatted to APFS or Mac OS Extended.

When you're ready, follow these steps:

1. Insert your USB drive into the Mac and open Finder.
2. Right-click your USB drive and select Encrypt [drive name].
3. Enter a strong and unique password, verify it and add a password hint.
4. Save your password in a secure place and begin the encryption process.

VeraCrypt (for Windows and macOS)

VeraCrypt is a free, open-source program that lets you use an encrypted USB stick across Windows, Mac and Linux. As Bitlocker isn’t available on Home editions of Windows, VeraCrypt allows you to password-protect an external drive without it.

To use VeraCrypt, follow these steps:

1. Download and install the right version of VeraCrypt for your operating system from the official VeraCrypt website. 
2. Insert your USB drive into the computer, open VeraCrypt and choose Create Volume.
3. Select Encrypt a non-system partition/drive and click Next.
4. Choose Standard VeraCrypt volume and select your USB drive.
5. If the drive is new or empty, select Create encrypted volume and format it. If the drive contains data, select Encrypt partition in place.
6. From here, you're able to choose the encryption type. Unless you want to experiment, we suggest AES or SHA-512.
7. Choose a strong and unique password, then select Format/Finish.

To use your password-protected drive in VeraCrypt, select a drive and choose Mount – the software will then make your USB drive accessible via File Explorer. When you're done, select Dismount.

Tips on choosing a password

There's no point in password-protecting your USB stick if the password itself is too easy to guess. If you're looking to create a secure password, remember the following:

• Don't use personal information – Avoid including your middle name, place of birth or your favourite sports team.
• Don't re-use passwords – Make the password tied to your USB stick unique.
• A passphrase is better than a password – It doesn't have to make sense, either – choosing three random words is a decent passphrase.
• Consider using special characters – For example, you could turn 'umbrella cable kitten' into '&umbrella+Cable!kitten*'.

For more advice on USB security, including popular password manager programs, see our guide on how to create secure passwords.

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