Lately, I’ve noticed quite a few stories and discussions online centering around the always popular debate about whether to use IMAP or POP3 for email. If you don’t know what I’m talking about, IMAP and POP3 are the protocols you use to access email via clients like Outlook, Thunderbird, or Android's stock email app.
The general consensus is that the more modern IMAP is the way to go and the aging POP3 standard should be abandoned at all costs.
But that’s just not the case. In fact, I am going to point out two very good reasons to go on using POP3, or perhaps even actively switch to it.
IMAP and POP3 basics
The key thing to know about the Internet Message Access Protocol (IMAP) is that it lets you view your email folders the same way on any device, as it’s all synchronized from a central server. With IMAP your inbox, sent, and customized folders look alike, and have the same content, whether you’re checking mail on your phone, tablet, or PC.
The Post Office Protocol version 3 (POP3), on the other hand, is specifically designed for downloading email from your email provider’s server to your local machine. Your actions aren’t synchronized with the server like they are with IMAP; it’s just a “dumb” download. Most (but not all) POP setups wipe email from their servers by default once you download it to your local device, although you can often configure your email client to leave your messages on the server as well.
As for set-up, it may be a little easier to use IMAP since many email clients create accounts with IMAP by default.
POP3, meanwhile, often requires a manual set-up. Making matters worse, IMAP-friendly email providers may not even support POP3, or if they do they may not publish detailed instructions on how to access your account using the protocol.
And that’s just on the server side. POP3 also requires your mail client to support it and not all do, such as Microsoft’s default mail client on the modern UI side of Windows 8.1.
It’s all about storage and privacy
The first reason you might want to use POP3 is if your main email account isn’t connected to a major webmail service like Gmail or Outlook. Alternatives such as email accounts from Internet Service Providers or website hosting services often set limits on how much mail can be stored on their servers.
In those cases, it’s best to turn to POP3, so you can download your mail and wipe it off the server to stay under the storage quota.
Privacy is another reason to rely on POP3. In this post-Snowden era, many are uncomfortable with keeping personal data like email on a third-party server. Email sitting on a server you don’t control is wide open to access by law enforcement with the right set of warrants.
Keeping your email on your devices, and off of third-party servers, means anyone who wants to look at your email has to come to you and not your email provider.
There are a few weaknesses to that argument, however, since intelligence agencies could still grab your email while it transits the Internet. Your mail provider may also have redundant backup copies of your email that won’t get deleted right away, defeating the whole point of using POP3 for privacy concerns. (Fortunately, it’s possible to encrypt your email.)
Sure, most of us are probably never going to be targets of a police investigation. But for most people these privacy concerns are really about the principle of the issue .
The downside of POP3 in a multi-device world is that you’ll have to take some precautions and think hard about how to access email on a mobile device.
Since the sole copy of your email is now on your PC, you’ll have to have a solid back-up plan to make sure you don’t lose your messages to a failed hard drive.
As for smartphones and tablets, you should still use IMAP there if possible, even if you’re using POP3 on your PC. The last thing you want to do is download email to both your phone and your PC via POP3, since you’ll end up with two separate repositories of email: stuff downloaded to your phone and stuff downloaded to your PC. It’s a nightmare.
If you’re using a major webmail service like Gmail, the easiest thing to do is just use Google’s Gmail app for Android or iOS. Ditto for Outlook.com and Yahoo Mail.
One last note about IMAP on your phone and POP3 on your PC: if you reply to email on your phone, your PC won’t download new messages in your sent folder, since POP3 only grabs messages from the server. So for POP3 users, mobile devices are better for viewing or deleting email, but not necessarily for sending messages you may need a paper trail for later.
Also, remember that if you leave your mail client running on your PC while you’re out, all mail messages could disappear from your phone as your desktop grabs new batches of email—unless you (usually manually) configure your email to continue to store messages on the server for a predetermined length of time after you download them.
It’s not a perfect solution, especially if you need mobile access, but if storage quotas or privacy concerns are issues for you, then POP3 is probably a better choice than IMAP.