POP3 vs. IMAP

Some of the most common questions our support team receives are:

  • What are the differences between POP3 and IMAP?
  • Does one have advantages over the other?
  • Which one should I use?

Let’s find out below.

POP3: Post Office Protocol (version 3, the current standard)

With a POP3 account your email software connects to the mail server and download email messages to your computer. Most of the time the emails are deleted from the mail server after being downloaded.

IMAP: Internet Message Access Protocol

With an IMAP account your email software leaves email messages on the mail server. IMAP allows you to view emails from the email softwares in multiple locations (such as home computers and office computers) without the need of transferring messages or files between them.

POP3IMAP
Pros
  • POP3 is a simpler protocol, easier to implement (from ISP point of view).
  • It is supported by more programs.
  • It clears the disk usage of that email account on the mail server (if copies of emails are not kept on the mail server).
  • IMAP is suitable for multiple users sharing the same email account.
  • It keeps emails in one location.
  • It keeps the email status (e.g. read or replied) on the message.
Cons
  • It can be tricky if multiple users use the same email account.
  • It keeps the incoming emails in a queue. If there is one big email stuck in the downloading process, the other emails can’t be viewed.
  • It takes up more space on the mail server and might incur extra disk usage charge.
  • It is harder to maintain IMAP at the server end.

In summary, if you’re office-based or only check your emails from one computer, POP3 is the way to go. You don’t have to worry about how much storage space you’ve used on the mail server. Your emails are deleted from the mail server as they reach your inbox. If you need to check emails from different computers, or you and other users share one email account, IMAP is the choice for you.