Use POP3 when:

• You predominantly use one device for emails. POP3 is ideal if you generally access your emails from a single device, such as a personal computer at home. It downloads all your emails to that specific device and deletes them from the server, allowing you to read them offline. However, any modifications you make to your emails (like deleting or moving them) will not reflect on other devices.
• You need to conserve server storage. If your email service provider allocates limited storage on their server, using POP3 can help manage this constraint effectively. By downloading emails to your device and removing them from the server, POP3 helps keep your server storage within limits.
• You prefer to manage personal backups. Emails are directly downloaded or stored on your device allowing you to have more control with backups. This can be helpful to make sure you get copies of your emails that are secure and retrievable even if there is a server issue.

Use IMAP when:

• You use multiple devices to check email. IMAP is ideal if you need to access your email from various devices, such as a smartphone, tablet, and computer, because it keeps your emails on the server. Any action you take (like deleting an email or marking it as read) is synchronized across all devices.
• You want to manage emails in real-time. IMAP allows you to see all your messages and their status (read, unread, replied, etc.) in real-time, no matter which device you’re using.
• You rely on a stable internet connection. Since IMAP requires an internet connection to access your emails (since they are stored on the server), it’s best if you have reliable internet access.