SMTP vs IMAP vs POP3: What’s the Difference?

Your search for an email client had just ended when you discovered a new hurdle. Your email client wants you to choose between IMAP and POP3. But you don’t have the slightest idea about what they are. Let’s discuss about SMTP vs IMAP vs POP3.

In this article, we’ll discuss email protocols, how they’re different, and how to choose the right one that fits your purpose. Let’s get started with SMTP vs IMAP vs POP3.

What is SMTP?

SMTP stands for Simple Mail Transfer Protocol. It’s the industry-standard protocol for sending emails. When you send an email from any email client, you’re almost certainly using SMTP.

With SMTP, you send, relay, or forward messages from an email client like Eltris to a receiving email server. Simply put, a sender uses an SMTP server to transmit an email message.

The key difference between SMTP and other protocols is that SMTP is solely used for sending emails. The SMTP protocol doesn’t come into play while receiving or retrieving emails.


While SMTP is the standard protocol included in all email services, you can choose a receiving protocol. When setting up an email client, you’ll get the option to choose between IMAP and POP3.

Both IMAP and POP3 manage incoming emails, but they differ in storage and accessibility. Let’s delve into the working of IMAP and POP3.

Post Office Protocol – Version 3 (POP3)

POP3 manages your email inbox like a post office. As you receive emails, it automatically downloads them on your computer and removes them from the email server. 

Therefore, your client-server saves a copy of your received emails locally on your system. Your emails are tied to a specific device, and you can access them without an internet connection. 

Some email clients, like Eltris, also give you an option to keep a copy of the email on the mail server. This way, both options – offline access and online, multi-device access – are available to you. 

A drawback, however, of POP3 is that it doesn’t sync emails, even if they are in the same thread. Each received mail is considered as a separate email and is stored separately. The same goes for any email folders you’ve created on a device or email client. 

In all, POP3 is suitable for you if you use only one email client to access your emails. Besides, it regularly removes emails from the mail server, thereby freeing up storage space. And since emails are not kept on your server, the risk of theft and privacy issues remains low.

Internet Message Access Protocol (IMAP)

Unlike POP3, IMAP stores your emails on the mail server. Most webmail services, like Gmail and Outlook, use IMAP. Since IMAP keeps the emails on the servers, you can access them from any device connected to the internet. And with mobile users making up for more than 60% of email traffic, it’s evident that email users are appreciating multi-device access.

In IMAP, you use the email client to connect to your mail server. Your mail server functions as the main storage where all your emails are stored. 

Because your emails reside on the cloud, you can easily access them from different devices. IMAP syncs all the newly received emails and changes. So, if you receive an email on an IMAP server, it’ll show up in your email client. And if you delete an email from your email client, it’ll be removed from your IMAP server. 

On the downside, mail servers have limited storage space. You will need to continuously empty your inbox to ensure ample space for receiving new emails. Also, your emails reside on online servers, making them vulnerable to theft and other security risks. 

IMAP can be an ideal choice for you if you have multiple email accounts. Or you prefer accessing your emails from various devices.

SMTP vs IMAP vs POP3 in Action

SMTP is the standard protocol for sending messages that comes with all email clients. Therefore, it doesn’t matter if you choose POP3 or IMAP, SMTP remains constant. 

When you send an email, your email client uses the SMTP server to send the message to the receiver’s email server. The receiver will then receive the email depending upon which protocol he uses for receiving.

If someone sends you an email, the same process will come into play. The sender’s email client will use SMTP to transmit the message to your email server. After successful transmission, your email client will fetch the message using IMAP or POP3. 

If you have IMAP, the message will remain stored in the mail server. If it’s POP3, the email will be downloaded onto your system, and the original email will be removed from the server. So, that is the main thing to note in SMTP vs IMAP vs POP3.

IMAP vs POP3: Which is Better?

Both protocols have pros and cons. In the end, it depends on how you want to store and access your emails. 

If you use a single device for your emails, say your business laptop, POP3 will be a suitable pick. It would store your emails on the device, so you’ll be able to access them even if you’re not connected to the internet. 

However, POP3 is more or less similar to disk storage. If something happens to your device, you’ll lose all your emails. To avoid this, be sure to configure your client to store emails on the server.

If you want to access and manage your email account from multiple devices and locations, IMAP is the best pick. Since it stores emails on the mail server, you can access them from anywhere as long as you’re connected to the internet. IMAP is ideal for business owners and remote workers who travel quite often. 

The drawback to IMAP is limited storage space. You’ll need to constantly empty your inbox to maintain adequate storage space for new emails. And because all emails are stored online, the risk of theft and breach remains severe. To avoid privacy and security risks, use an email client like Eltris that offers robust encryption and spam & virus protection.

Wrapping up: SMTP vs IMAP vs POP3

Let’s quickly wrap up what we’ve covered in this post regarding SMTP vs IMAP vs POP3.

SMTP is the standard email sending protocol. No matter what email client or receiving protocol you choose, SMTP remains constant. 

POP3 and IMAP are the two email receiving protocols. POP3 stores your emails on the device and deletes them from the server. You can, therefore, access them without the internet. But you can only access them from one device.

IMAP stores your emails on the email server. It allows you to access emails from anywhere, but you may run into storage and security issues. 

The best pick? Pick an email client like Eltris that offers both POP3 and IMAP.