POP3 vs. IMAP

When you set up a new email account, you get a choice about what kind. The typical choices are:

  • iCloud
  • Exchange
  • Google
  • Yahoo!
  • AOL
  • Other Mail Account…

Unless you’re email is hosted by iCloud, Exchange, Google, Yahoo, or AOL, you will choose Other Mail Account…and then you’ll get to choose between two kinds of email account, POP3 and IMAP.

What’s the difference? Why should you choose one or the other? Each has advantages and disadvantages.

POP3

If your email account is set up as a POP3 account in your email program, each time you receive new messages they will be copied from your email provider’s mail server to whatever device is receiving the messages…your computer, your phone, or your tablet. Each of those devices store the messages in a storage folder within their own storage device…hard drive, solid state drive, or flash memory. A certain period of time after the new messages are received, they are deleted from the email provider’s server.

Since each device copies the message from the mail server separately and stores its own copy on its own internal storage, deleting a message on one device doesn’t delete it from the other devices…you have to do it separately on each device. Moving the message to a different folder on one device doesn’t move it on the other devices…you have to do it on each device separately.

If you send a message on one device, the sent message is stored on that device…but not on any of your other devices.

POP3 was the original way email accounts used to be set up in the earliest days of the internet, when everybody’s email was hosted by either AOL, Yahoo, or Prodigy. Why? Because the fact that received messages were removed from the mail server meant that those email providers didn’t need to provide very much space on their server for each account. So it was a benefit to the email providers.

Today, the primary benefit in POP3 mail is that since the messages are stored right on your computer, phone, or table, you can access them even when you have no internet connection.

IMAP

If your email account is set up as an IMAP account in your email program, all of your messages are stored your email provider’s mail server. You email program on each of your devices always shows you the messages stored on the mail server…so all the devices are always the same. When you delete a message on any of your devices, it actually deletes the message on the mail server…so it’s automatically deleted from your other devices. If you move a message to a different folder on any device, it’s moved on the mail server, so all your other devices also show it as having moved to the other folder. And when you send a message, it’s stored in the Sent folder on the mail server, so you can see your sent messages on all your devices.

Having all your devices coordinated automatically is a huge benefit. But there’s more. Suppose your phone, tablet, or laptop is lost or stolen. You get a new device and set and set up your email account…and VOILA! All your messages pop right in, just as they were on your old device. Same if you just decide to replace your computer, phone, or tablet with a new one, or move from a PC to a Mac or visa versa…the mail just comes in.

The downside of IMAP is that, obviously, your messages take up much more space on the mail server…and some email providers may charge more for that extra space.

For most people who have more than one device they are using for email, IMAP is the better choice.