POP3 vs IMAP, which one should you choose?

This FAQ will teach you about the POP3 and IMAP email protocols

Learn all about the POP3 and IMAP email protocols with this 123-reg knowledge video.

Tip: IMAP allows you to check your email from multiple devices and always see the same messages, as these stay on the server.

POP3 and IMAP are protocols used to connect your mailbox server to an email client. including Microsoft Outlook or Mozilla Thunderbird, a mobile devices such as iPhones and Andriod devices, tablets and online webmail interface such as Gmail, Outlook.com or 123-mail.

POP3 stands for Post Office Protocol and has been around for many years. POP3 downloads your mail as you view it on your email client. It’s great for users who only want to access their mail from one client.

IMAP stands for Internet message access protocol and simply connects to the mailbox and allows you to view your email rather than downloading it. It is a more modern email protocol and is designed to support our lifestyles by allowing you to easily view email from multiple locations. Unlike POP3, your emails will be synced, so if you delete an email in one client and then check it on an alternate client it will also be deleted.

What settings am I using? POP or IMAP?

When you first set up your email with your email client or device you will have been asked to enter incoming server details, this will have either been pop.123-reg.co.uk or imap.123-reg.co.uk. As the names suggest, using pop.123-reg will mean that you are using the POP protocol, whereas imap.123-reg means you are using IMAP.

You may also be able to see this setting in the account information section of your chosen client. 

Should I still be using POP?

If your email configured using the POP email protocol, with the option “leave messages on server” enabled, it means that when you receive an email you download a copy of the email to your device or email client whilst leaving a copy of the message on the email server.

This method of serving emails is out-of-date and continuing to use it may cause issues with your email service. This is because the POP email protocol was never designed to be used in this manner. While POP will work for now, continuing to use it may cause issues as email platforms move further away from this protocol.

To speed up your mailbox and reduce the risk of losing email, we strongly recommend that you switch to the IMAP email protocol now. Simply put, IMAP was designed to enable users with multiple devices and clients to access their email across different locations, using the email directly from the server; a far easier and efficient was to serve email.

Changing to IMAP is a very easy process and should be done as soon as possible to ensure that your email continues to work correctly. We ask that you set up your email again for your email client and mobile devices using the IMAP protocols, which means setting your incoming server address to imap.123-reg.co.uk.

We have the full instructions to help you set up your email on the most popular email clients, and the most popular mobile devices.

Once you have set up using the IMAP protocol, please ensure you delete your POP email connection.

Please note that with POP, email is stored on your email client so will be stored locally on your computer. This means that you will not lose any email by deleting your POP connection.


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