What is IMAP server?

What is IMAP server? IMAP enables users to access their email messages regardless of location and time. The reason is that it is accessed through the internet because the emails are stored on servers.

Updated: 09 May, 22 by Susith Nonis 6 Min

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What is IMAP server? Anyone with previous experience setting up an email account has probably encountered the question about the email protocol they would like to use, whether IMAP or POP. If you are one of the few that have never set up an email before, this question might be puzzling. The option you decide on greatly impacts receiving, sending, and overall using your email. In the past, Post Office Protocol, commonly known as POP, was the most popularly-used email protocol.

Nowadays, most people opt for IMAP. But what is the meaning of IMAP? It stands for Internet Message Access Protocol. As this name implies, IMAP enables users to access their email messages regardless of location and time. The reason is that it is accessed through the internet because the emails are stored on servers. Each time you open your inbox, your email client has to contact this server to connect you to your email messages.

When you access your messages via IMAP, you are not downloading or accessing them on your computer in the actual sense. Rather, you are reading them right off the server. Due to this, you can access your email from various devices without losing anything because your emails are not tied to a singular device.

If you use popular email services such as Outlook or Gmail, any alterations made to your email messages are automatically synced with the server. This is also the case with IMAP. Whenever you decide to set up an account with a general email application, the latter usually automatically configures it as an IMAP account. Consequently, when you make any changes in the email app, they will automatically be synced with this webmail server. 

Sometimes, the email client might have trouble configuring your webmail as an IMAP account. If this occurs, you should get in touch with their customer support to receive guidance on setting up this account manually. IMAP works as an intermediary between the email servant and the email client.

Some people think POP and IMAP are interchangeable, which could not be further from the truth. POP functions by contacting an email server and downloading all new email messages from this server. Once downloaded, they disappear from the server. So, if you try to check your inbox from another device, the previously downloaded messages will no longer be available. POP is only ideal for people who primarily access their emails from a particular device.

If you travel more regularly or have to access your email from different devices, an IMAP-based service is more effective. It will help you avoid having a different email inbox with each device. Overall, POP is not concerned with syncing your email server and client.

With IMAP, you can access, read, sort, and organize your messages before even downloading them. It makes the protocol fast and efficient. IMAP also keeps records of all sent messages, allowing users to access them from any location.

You don't need to download or store your emails on your local device because IMAP isn't tied to a single device. Therefore, you can open your inbox using different devices such as your smartphone, iPad, laptop, or desktop PC. An IMAP operation takes certain general processes and steps:

  • When someone signs into the client, such as Microsoft Outlook, the email client uses IMAP to contact the email server (IMAP Outlook).
  • This connection is made on a particular port.
  • The email client displays all the email headers.
  • Once the user clicks on the message, IMAP downloads it to the client. No attachment is downloaded automatically. It only happens after the user's request.
  • Users are able to access their messages more quickly with IMAP servers than with different retrieval protocols such as POP3.
  • The email messages are stored on the server and remain there unless the user deletes them.


Most IMAP implementations support several logins. It makes it possible to connect to an email server from multiple devices simultaneously. For example, you can access your Gmail from your desktop app as well as from your Android smartphone's Gmail app. One doesn't have to be concerned about emails disappearing from servers when using different devices. You also don't need to restrict yourself to always using one device.

IMAP offers major levels of flexibility to users that need to access their emails often from different locations and different devices. That is ideal for regular travellers as they are in different locations most of the time.

The protocol does not specify the details for handling several connections simultaneously. Instead, this is left to the developers of the email client.

Here is a summary of all the benefits of the IMAP protocol:

  • Offers fast and efficient access
  • Users can access their emails from multiple devices.
  • Users can organize their email messages on the servers by forming folders and subfolders.
  • IMAP servers support IDLE extensions, which are also known as push mail. Hence, the emails read unread in the inbox, eliminating any need to create a polling interval. Users don't have to first click receive either.
  • IMAP can be used when users are offline
  • The default IMAP port is port 143.


Although IMAP comes with an authentication mechanism, it is fairly easy for someone with the expertise on how to steal passwords using a protocol analyzer to circumvent the process. That is seeing as clients' usernames, and passwords are transmitted as cleartext.

Administrators can also take advantage of this security flaw by utilizing SSL encryption.

Generally, the IMAP email retrieval protocol is very popular among users. Its popularity is growing, and this is predicted to be the trend in the coming years. The main reason for its popularity is the proliferation of mobile devices like iPads and smartphones. While other client-server mail retrieval protocols like POP can be likened to "store-and-forward" services, the IMAP server is more of a remote file server. 

We hope that this article helped you clear out the question of what is IMAP? In case you want to access your email with ease while on the go, the latter is your best bet.

Susith Nonis

Susith Nonis

I'm fascinated by the IT world and how the 1's and 0's work. While I venture into the world of Technology, I try to share what I know in the simplest way with you. Not a fan of coffee, a travel addict, and a self-accredited 'master chef'.