Password-Protect Mac PDFs

For a simple way to password-protect a PDF on your Mac, use the built-in Preview application. Open the PDF (or other file) in Preview, then choose File> Export.

Preview>Export>PDF>Encrypt

In the dialog box that appears, click on Encrypt, type in your desired password, and click Save.

If you don’t change the name or location of the file, the existing one will be overwritten with your password-protected version.