Both POP (Post Office Protocol) and IMAP (Internet Message access protocol) allow people to get access to their email from a remote server; however, that is where most similarities end. POP simply downloads email to your computer, and usually (but not always) deletes the email from the remote server. The problems arise if you have more than one device where you read your mail (desktop, laptop, tablet or phone). Here's why it's bad: You have to delete or file the same email on every device

Logging into each device, you will see lots of unread emails with no indication of which you deleted, read, flagged or filed Any folders you created and organize on one device won't be replicated on the other devices

IMAP allows users to store their email on remote servers. This two-way protocol also allows the user to synchronize their email among multiple devices, which is extremely important today, when most people have at least two devices - their laptop and smartphone.

How Do POP & IMAP Compare?

The two protocols are best compared by looking at their most basic workflows.

POP Workflow:

  • Connect to server
  • Retrieve all mail
  • Store locally as new mail
  • Delete mail from server*
  • Disconnect

*The default behavior of POP is to delete mail from the server. However, most POP clients also provide an option to leave a copy of downloaded mail on the server.

IMAP Workflow:

  • Connect to server
  • Fetch user requested content and cache it locally, e.g. list of new mail, message summaries, or content of explicitly selected emails
  • Process user edits, e.g. marking email as read, deleting email etc.
  • Disconnect

As you can see, the IMAP workflow is a little more complex than POP. Essentially, folder structures and emails are stored on the server and only copies are kept locally. Typically, these local copies are stored temporarily. However, you can also store them permanently.

 

 

What Are The Advantages Of POP?

Being the original protocol, POP follows the simplistic idea that only one client requires access to mail on the server and that mails are best stored locally. This leads to the following advantages:

  • Mail stored locally, i.e. always accessible, even without internet connection
  • Internet connection needed only for sending and receiving mail
  • Saves server storage space
  • Option to leave copy of mail on server
  • Consolidate multiple email accounts and servers into one inbox

What Are The Advantages Of IMAP?

As mentioned in the introduction, IMAP was created to allow remote access to emails stored on a remote server. The idea was to allow multiple clients or users to manage the same inbox. So whether you log in from your home or your work computer, you will always see the same emails and folder structure since they are stored on the server and all changes you make to local copies are immediately synced to the server.

As a result, IMAP has the following advantages:

  • Mail stored on remote server, i.e. accessible from multiple different locations
  • Internet connection needed to access mail
  • Faster overview as only headers are downloaded until content is explicitly requested
  • Mail is automatically backed up if server is managed properly
  • Saves local storage space
  • Option to store mail locally

 

What Is The Best Email Protocol For Me?

Obviously, it depends on your specific variables and you probably have an idea of what is best suited for your situation already. The points below should help to make a final decision.

Choose POP If…

  • you want to access your mail from only one single device
  • you need constant access to your email, regardless of internet availability
  • your server storage space is limited

Choose IMAP If…

  • you want to access your email from multiple different devices
  • you have a reliable and constant internet connection
  • you want to receive a quick overview of new emails or emails on the server
  • your local storage space is limited
  • you are worried about backing up

If in doubt, go with IMAP. It’s the more modern protocol, it allows you to be flexible, your email is automatically backed up on the server, available server space usually isn’t an issue these days, and you can still store important emails locally.