How to password protect PDF files on your Mac

Locked PDF icon

Password protecting your PDF files is a great way to keep the contents from being revealed to those who you never intend to see them.

This great security feature can be taken advantage of right from the Preview app that comes bundled with your Mac, and in this tutorial, we’ll show you how you can use it to enhance the security of your PDF files.

Why to password protect a PDF document

You may want to password protect a PDF file if you intend to send the file to one individual only, but don’t want others to be able to open the file and see its contents.

With a password protected PDF file, you only only need to send someone the PDF file, and then let them know what the password is to get into it. Anyone who doesn’t have the password will be unable to open the PDF file, which keeps it safe from prying eyes.

Some scenarios where a password-protected PDF document may be useful include:

  • Sharing login credentials with an individual
  • Keeping top-secret business plans between you and a business partner
  • Preventing multiple users on a computer from seeing a file meant for one person
  • And more…

Password-protecting a PDF file with Preview on your Mac

So if you’ve made it this far, then the idea of password protecting your PDF files on your Mac probably sounds like a good idea to you. If so, we’ll start getting into the meat and potatoes of how this is done right away…

1) Locate the PDF document you wish to password protect.

password protect PDF Mac document

2) Open the PDF file in the Preview app by right clicking on the file and choosing Open With > Preview.

password protect PDF Mac - preview app

3) Once open in the Preview app, go to the Menu Bar and choose File > Export….

password protect PDF Mac - export

4) From the export sheet, put a check mark in the Encrypt box, and enter a password you wish to lock it with.

password protect PDF Mac - encrypt

5) When satisfied with the password you picked, click on the blue Save button.

That’s all there is to it! Now you have a password-protected PDF file. Warning: share the password wisely.

Okay… now what?

Now that you have password protected your PDF document, what happens when someone tries to open it?

First of all, the icon for the file changes. You’ll see that the icon now has a lock on it, indicating that it’s a locked PDF file:

Locked PDF file Mac

After double-clicking on the PDF file, the other person (and yourself) will be prompted to enter the password to get in. If they do know the password, they can see the contents of the PDF file, but if they don’t, then the file will remain locked from their view.

Enter Password for PDF on Mac

And that’s all there is to it. Easy enough right?

Wrapping up

You should make password-protected PDFs as much as possible to keep confidential information safe. Sometimes, important files can be compromised or stolen by people who you don’t intend to see them. This can be a huge security risk.

What’s more is you should never send the password in the same email or other file-sending technique that you send the PDF file in. That would be pointless because anyone who sees said email will know how to get in.

Instead, it’s more secure to email the file to someone, and then text them the password, or send the password over a totally separate communication medium as a second layer of security.

Other useful related posts about PDF files:

Will you be password-protecting your PDF files from now on? Share in the comments below or visit us on Twitter!