What is the difference between IMAP and POP3?
We receive this question regularly through our support desk. In this article, we'll explain when you should choose IMAP and when POP3 is the better option.
But let's start at the beginning: what exactly are IMAP and POP3? What they have in common is that they are both standardized protocols used by your email application (such as Microsoft Outlook or Apple Mail) to communicate with your mail server and retrieve your email.
The main difference is that IMAP keeps your email client and the mail server synchronized, while POP3 simply downloads your email.
What is POP3?
POP3 is a simple way for an email application to retrieve email from a mail server. It only downloads messages that have not previously been retrieved by the email application. You can also choose whether downloaded messages should be removed from the mail server.
For example, you could configure your email application to delete messages from the server only after 14 days. This allows new emails to be downloaded by multiple devices during that period. However, emails that you send are not synchronized back to the mail server or to your other devices.
What is IMAP?
With IMAP, your email application and the mail server stay synchronized. If you delete an email in your email application, it is also deleted from the mail server. Any folders you create, along with the emails they contain, are also synchronized and stored on the mail server and all your other devices. Sent emails are likewise synchronized through the mail server, making them available on all your devices.
For example, if you regularly check your email on your smartphone, tablet, and computer, and you delete an email on your smartphone, that email is also removed from the mail server. Once it has been deleted from the server, it will also disappear from your tablet and computer the next time those devices synchronize with the mail server.
IMAP vs POP3: the key differences
| IMAP | POP3 | |
|---|---|---|
| Email remains on the server | Yes | No (unless configured otherwise) |
| Synchronizes across multiple devices | Yes | No |
| Folder structure synchronized | Yes | No |
| Sent email visible on all devices | Yes | No |
| Requires server storage space | More | Less |
| Works without an internet connection after downloading | Limited | Fully |
Which should you choose: IMAP or POP3?
IMAP is the obvious choice if you check your email on multiple devices and want to see the same inbox, folders, and read/unread status everywhere. POP3 is better suited for people who use a single device or prefer to store their email locally rather than on the mail server, for example to save storage space on the server.
