POP, IMAP, and SMTP: which one to use to set up email?

Posted by jason stewart on March 11th, 2020

New forms and channels of communication seem to multiply in the technological moment in which we live. However, e-mail remains firm and strong as one of the most used means of communication worldwide, especially in corporate environments. When setting up an email service for the first time, it is common to find terms such as POP, IMAP, and SMTP.

Although it is strange to the first contact, these terms are fundamental for us to receive and send emails using any device, such as computers, smart phones, and others.

If you are faced with the need to set up an email but are not sure what these acronyms mean, you are in the right place! Learn here what POP, IMAP, and SMTP mean and find out which option is the best email hosting for you.

What POP, IMAP and SMTP mean

To choose an option it is essential to understand what each of these acronyms means, as well as their implications. Before proceeding, it is worth mentioning that POP, IMAP, and SMTP are e-mail protocols. The protocol is a convention, that is, a type of agreement that defines the rules of something. In this case, these are the rules for sending and receiving e-mails.


POP or POP3 is the procedure used by cheap email hosting to download emails and messages from a server. When using the POP protocol, a computer program - or application - connects to the server and downloads all existing messages since the last scan. After downloading, messages may or may not be deleted from the server, depending on the configuration chosen by the user.

The acronym POP comes from Post Office Protocol and it is also known to be an offline protocol. This is because, once the messages are downloaded from the server, it is possible to read the emails without an internet connection.

What is IMAP

 IMAP is the protocol used for synchronization between a program/application and the email server. When using the IMAP protocol, the program connects to the server and synchronizes all messages and other settings on the server. Unlike the POP protocol, IMAP allows you to synchronize folders and other message markings, such as tags, for example. Thus, the program used to read the email will be a mirror of the messages and their organization on the server.

The acronym IMAP comes from Internet Message Access Protocol, whose translation would be something like "protocol for accessing internet messages". This protocol allows greater control of the e-mail box, presenting other advantages, as we will see later.

What is SMTP

SMTP is the protocol used for sending e-mails. This protocol only allows the sending of e-mails, it is not possible to use it to retrieve messages on the server. The acronym SMTP comes from Simple Mail Transfer Protocol, which would be something like “simple mail transfer protocol”.

As we can see, the SMTP protocol will always be used in conjunction with another protocol, POP or IMAP, so that it can be possible to read and send e-mail messages daily. The exception is in charge of the mass mailing tools (email marketing) which, in this case, do not require a protocol for receiving emails, only for sending.

POP or IMAP: when to use and which one to choose? 

The choice between POP and IMAP protocols is made whenever there is a need to configure a program for receiving emails.

This includes both computer programs, such as Microsoft Outlook and Mozilla Thunderbird, as well as applications for smartphones and tablets, on any operating system (Android, iOS, and others). These programs and applications depend on the protocols for sending (SMTP) and receiving (POP or IMAP) e-mails to work.

The exception is webmail, which is a feature provided by email providers to use the service directly in the browser. In that case, you can receive and send emails without the need for any additional configuration. When using webmail, the reading and administration of e-mails take place directly on the server, without any messages being downloaded or copied to an application used by the user. The downside of webmail is that it can only be used in the browser, which can slow down its operation, depending on some circumstances.

Now that we understand which situations protocols are needed, it is time to decide which one to choose in each case. Like everything in life, every choice has its advantages and disadvantages. We will see below some situations that may be more advantageous (or not) in each of the options.

Situations in which POP can be indicated (to receive e-mails

 Choose POP if you:

 You want to download all messages received from the server. 

You want to be able to read your emails even without being connected to the internet all the time.

It has little space for storing e-mails on the server. 

You want to allow access to email only on a specific device. Especially useful for companies that want to avoid receiving and sending emails outside of work hours and / or the workplace. It is worth mentioning that other methods can be used for this purpose, such as a VPN, for example.

Advantages of using POP:

Once downloaded, all e-mails are available on the user's device, even at times without an internet connection.

You can spend very little space for storing emails, as long as the program is configured to delete messages from the server after downloading.  In your server colocation service provider, there is a backup of all emails on the user's device.

 Disadvantages of using POP:

If the user has problems with his device and does not have a copy (backup) of the emails, there is a risk of losing all messages.

POP allows you to download only messages in your inbox. If there are other folders in webmail, they will not be visible in the email client program. 

In accounts used by more than one person, such as a team email, for example, POP can confuse because there is no synchronization between the email programs and the server.

Situations in which IMAP may be more suitable (for receiving e-mails)

 Choose IMAP if you:

Receive and send e-mails through more than one device, such as a computer and a Smartphone. 

You want to have more control over the organization of messages on the server, creating folders and classifications that are reflected on all devices.

Shares the same email account with other users. This situation is especially common in generic emails such as contato@dominio.com, sales@dominio.com, etc.

 There is enough space on the server to store all emails.

Advantages of using IMAP:

 In case of problems with the device, no email is lost, as they are safe on the server. Especially if you have the best dedicated server hosting uk services. 

Synchronization with the server ensures that all devices and / or users are viewing the same inbox, folders, and other settings.

Disadvantages of using IMAP:

 All messages and attachments consume server storage space, which can be an issue with plans with little available storage space.

It may not be possible to read all messages if there is no internet connection at that time.

Who uses email a lot and wants to have more resources, IMAP is certainly the best option. However, in some cases, the use of e-mail by the hosting server also consumes the space dedicated to your website. To get around this, you can hire a separate email service, such as Google's G Suite.

SMTP: when to use 

As we saw earlier, SMTP is always used for sending e-mails, regardless of the protocol chosen for message retrieval (POP or IMAP).


 As we saw here, the protocols for receiving and sending e-mails are essential to make use of e-mail in programs and / or applications installed on the user's device. And the choice of the protocol can be more or less interesting depending on the purpose and type of use that you want to make of the e-mail service.

POP, or POP3, use a download process to retrieve messages from the server, without synchronizing any settings or directories. It may be more interesting for people who don't have much space to store emails on the server. However, if the device containing the messages is defective, there is a risk of losing all emails.

IMAP is a more sophisticated protocol that synchronizes the email server with all user programs and applications. For users with a constant internet connection, it is certainly a more interesting option and with more possibilities. Only the storage space issue should be noted, as all messages will be stored by default on the server unless they are

SMTP, in turn, is the standard option for sending e-mails. Many colocation uk are providing exceptional services. 

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jason stewart

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jason stewart
Joined: February 24th, 2020
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