Changing from POP Email to IMAP on Apple Devices

Many older email accounts were originally set up as POP accounts. POP can work well on a single computer, but it often causes confusion when the same mailbox is used on several devices. Messages may appear on one device but not another, sent items may only exist on one machine, and it becomes harder to keep everything organised.

IMAP works differently. With IMAP, the email stays synchronised with the mail server, so your inbox, sent items and folders can remain consistent across your iPhone, iPad and computer.

In most cases, IMAP is the best choice for clients using multiple devices.
New messages, sent items and folder changes can then be seen everywhere rather than being stored separately on each device.

POP and IMAP - what is the difference?

POP	IMAP
Downloads email to one device	Keeps email synchronised across devices
Sent items may only exist on the device that sent them	Sent items can appear on all devices
Deleting or filing mail on one device may not affect others	Changes usually appear on all connected devices
Often used in older setups	Usually best for modern multi-device use

Can I move to IMAP without bringing back thousands of old emails?

Yes. In many cases the simplest approach is to make a fresh start with the mailbox and then set up the email account again as IMAP.

This means:

the mailbox is reset or cleared,
the account is re-added as IMAP on the devices,
new email going forward stays synchronised properly,
older POP email can remain available locally on the original device where it was downloaded.

Important: if old emails are not copied into the new IMAP account, they will not automatically appear on all devices afterwards. They will usually remain only on the computer or device where the POP account originally stored them.

Will I still be able to see old sent items?

Usually, yes.

If a sent email was created while the account was set up as POP, that sent item is often stored locally on the device that sent it. So if the user sent those emails from the MacBook, they will generally still be visible there afterwards, provided the old local mail data is not deleted.

However, those old sent items will not normally appear on the other devices unless they are deliberately copied into the IMAP account.

Please note: do not delete the old POP mail data until you are certain that any important historic messages are still available where you need them.

Typical example

A client has:

an iPhone,
an iPad,
a MacBook,
Apple Mail,
and possibly Thunderbird on the MacBook.

With the old POP setup, each device may have built up a slightly different view of the mailbox over time. One device may have emails that another one does not. Sent items may be present on the MacBook but not on the phone or tablet.

After moving to IMAP, only the new IMAP account should be used for day-to-day email going forward.

Recommended low-risk migration approach

Check which device holds the most complete historic mail.
In many cases this is the MacBook.
Keep a local archive of the old POP account.
This allows the client to refer back to older inbox and sent items if needed.
Reset or clear the mailbox if starting fresh is preferred.
This avoids thousands of old messages reappearing in the active mailbox.
Re-add the account as IMAP on all devices.
Going forward, email then stays in sync properly.
Make sure only the IMAP account is used for new email.
The old POP account should be treated as archive only, or removed once it is no longer needed.

What about Apple Mail and Thunderbird?

Apple Mail

Apple Mail can usually keep local mailboxes on the Mac even after a new IMAP account has been added. This makes it a good place to retain older POP-based emails for reference while using the IMAP account for current work.

Thunderbird

Thunderbird can also retain old local folders from previous POP use. This can be useful if the client has sent items or historic folders there which still need to be consulted occasionally.

Good practice: rename the older local folders clearly, for example Old POP Archive or Previous Sent Items, so the client does not accidentally continue using the wrong account.

Best advice for clients wanting a cleaner setup

If the mailbox currently contains very large quantities of older email and the client is happy to start afresh, a reset followed by a clean IMAP setup is often the most straightforward solution.

This avoids:

bringing back thousands of unwanted messages,
slow synchronisation during migration,
duplication problems,
confusion between old POP mail and new IMAP mail.

It also means that from the point of migration onwards, the client can enjoy a properly synchronised mailbox across all devices.

Points to remember

Old POP messages are often stored only on the device that originally downloaded them.
Old sent items may remain visible on the MacBook or original sending device.
Those old items will not automatically appear on the new IMAP mailbox unless copied there.
For daily use going forward, the IMAP account should be the only live account used.
Before making changes, it is wise to confirm that any important old messages are still accessible somewhere safe.

Need help with POP to IMAP migration?

Seren Web can help configure email accounts on Apple devices, Apple Mail, Thunderbird and other email applications, while helping clients reduce the risk of losing important access to older messages.

Contact Seren Web for email migration help

Seren Web Help Guide

This guide is intended as general advice. Exact behaviour can vary depending on how the original POP account was configured, which device downloaded the messages, and whether sent items were stored locally or on the server.