For most users, IMAP is the better choice since emails stay synced across smartphone, tablet, and PC. POP3 only makes sense if you use a single device or want to save server storage.
Audio & media
IMAP / POP3: Definition & explanation
In a nutshell
IMAP and POP3 are protocols for retrieving email from a server. IMAP keeps mail synced across devices, while POP3 downloads messages and often removes them from the server.
How does IMAP / POP3 work?
IMAP (Internet Message Access Protocol) and POP3 (Post Office Protocol version 3) define how a smartphone or email client fetches messages from a mail server. With IMAP, emails stay stored on the server and the device only displays a synced copy. Any action—reading, deleting, moving—is mirrored across all connected devices, making it ideal for multi-device use. POP3 instead downloads messages to a single device and, by default, deletes them from the server afterward, unless the 'leave a copy on server' option is enabled. Both protocols work alongside SMTP, which handles sending mail. Modern smartphones and providers mostly default to IMAP because it supports folder structures and multi-device syncing far better. POP3 still has a niche when server storage is limited or only one device is used to access mail.
Advantages of IMAP / POP3
- IMAP: syncs across all devices
- IMAP: keeps folder structure intact
- POP3: minimal server storage needed
- POP3: mail available offline locally
Disadvantages of IMAP / POP3
- IMAP: requires server storage
- IMAP: no new mail without internet
- POP3: no sync between devices
- POP3: emails can be lost accidentally
Frequently asked questions
Yes, usually you just switch the account settings to IMAP or re-add the account in the app. Emails already downloaded via POP3 need to be backed up or imported separately.
Both protocols are unencrypted by default but are typically secured today via SSL/TLS connections. Make sure your email client uses encrypted variants (IMAPS/POP3S) to protect data from phishing and eavesdropping.
Guides with IMAP / POP3
No linked guides for this term yet.