What is POP3?

POP3 (Post Office Protocol, version 3) is a protocol for downloading email from a server to a single device. By default it pulls messages down and deletes them from the server, treating your local device as the one true mailbox.

How POP3 works

A POP3 client connects (typically on port 995), downloads any waiting messages, and — unless configured to leave a copy — removes them from the server. There’s no folder sync and no shared state across devices.

POP3 vs. IMAP

POP3 is simpler and older than IMAP. Use POP3 if you want mail on one machine and don’t need it synced; use IMAP if you read from multiple devices. Both are about reading mail — SMTP handles sending. For test automation, a REST API that returns parsed messages is usually easier than either protocol; see receiving email with an API.