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Comparisons · IMAP / POP3

IMAP vs POP3: Multiple Devices, Server Storage, and Backup

IMAP keeps emails and folders on the server and syncs read, moved, and deleted messages. POP3 mainly has a setting to import new arrivals to the PC and delete them from the server.

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IMAP vs POP3: Multiple Devices, Server Storage, and Backup overview: Comparison criteria, Choosing for your situation, First steps to try, Operational notes
An overview of this guide’s steps and checks, not a screenshot of the app.

Who this guide is for and what to prepare

  • People who want to know the difference between IMAP/POP3
  • People who want to start with a small, safe test

What you need

  • Make a test copy leaving the original data
  • Check the compatibility conditions and storage location of the destination

Comparison criteria

IMAP keeps emails and folders on the server and syncs read, moved, and deleted messages. POP3 mainly has a setting to import new arrivals to the PC and delete them from the server.

Scroll horizontally to see the full table →

Comparison criteria
standardIMAPPOP3
keepServer-centricLocal focus
multiple devicesstate synchronizationDifficult to match
deleteReflected on all devicesBe careful to delete after receiving

Choosing for your situation

IMAP for PC, smartphone, and web use. Consider POP if you have requirements for consolidating to a specific PC and local backup operations.

IMAP is an easy choice for individuals and teams who go back and forth between PCs, smartphones, and web mail on a daily basis. In existing operations where lines are limited and received items are consolidated onto one device, POP may remain, but the sent information and folder status will not be automatically collected. POP's "Delete from server" may delete emails before other devices receive them, so users do not understand the settings and do not switch to an existing account. For method migration, add it as a separate account.

First steps to try

Check whether the read/moved information is reflected on the web using IMAP. For POP, read ``Keep it on the server'' and when to delete it, then try just one message.

  1. Check the IMAP/POP server name, port, and encryption method on the email provider's official page.
  2. Add as IMAP to Thunderbird and move exam email to read/separate folder
  3. Check if read/move is reflected in webmail and smartphone
  4. When verifying POP, enable [Leave messages on server] and the number of days to delete and receive only one test email.
  5. Back up your Thunderbird profile and open saved emails and attachments

Operational notes

To change the method, add it as a separate account. Back up the profile and check the number and attachments. IMAP also requires independent maintenance.

Limitations and requirements

  • Check the POP server deletion settings
  • IMAP deletion will also be reflected on other devices

Frequently asked questions

Does IMAP require backup?

Separately maintained in case of synchronous deletion.

Changed from POP?

Add IMAP and move it after backup.

Official sources and verification date

Sources checked: . Check the official sources below for changes to supported systems, plans and menus.

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