Last updated: 26 October 2026
Adding a password to a PDF is a simple way to keep payslips, contracts, medical letters and ID documents private when you send them by email or store them in the cloud.
An open password (sometimes called a user password) is required to view the document at all. Without it, the file's contents are encrypted and unreadable.
A permissions password (owner password) lets anyone open the file but restricts actions such as printing, copying text or editing. These restrictions are respected by mainstream PDF readers but are easier to bypass, so use an open password whenever confidentiality really matters.
Never send the password in the same email as the file. Share it through a different channel — a text message, a phone call or a messaging app — so someone who intercepts one doesn't automatically have both.
If you later need to remove the password from a document you own, the Unlock PDF tool will do that once you supply the correct password.