Multiple Ways to Import Emails to Thunderbird

[gloris]

 See there are multiple ways via which you can import emails in Thunderbird.  It all depend upon the source. Let me explain 

For Eg: You have emails stored on an IMAP server - you can import them into Thunderbird by simply connecting the IMAP account via the "Add Account" option under the menu. 

On the other hand if you want to Import emails from files such as EML, MBOX etc. like that you will need some extra support. 

MBOX can be imported directly in the local folder without any extension while adding in Mail Folder under the profile and also for people with low technical skills once can - also use ImportExportTools NG. For EML files you will additionally need ImportExportTools NG there is no other way - except a very long walk around using and email client that supports both. Although it is great it is limited to only 4GB of import. 

And also additionally one can also use Third Party Thunderbird Import Tool eg: By BitRecover that specialise in dealing with bulk data with integrity 

[Jon]

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[lucifer_tech]

Hi,

If you're looking to import emails into Thunderbird, the method depends on the email format you're working with. For example, EML files can often be imported using add-ons, while MBOX files can be imported with Thunderbird's built-in Import feature (in newer versions) or compatible extensions. If you're migrating a large mailbox, manual methods can become slow and may not always preserve the folder hierarchy correctly.

For bulk imports, I found SysTools Thunderbird Import Wizard to be a much more convenient option. It allows you to import multiple MBOX files into Thunderbird in one go while maintaining the original folder structure, email formatting, attachments, and metadata. It's especially useful if you're migrating from clients like Apple Mail, Eudora, Opera Mail, or any other application that stores emails in MBOX format.

[davidmithen]

The easiest way to import emails into Thunderbird varies, depending on the format of your existing mailbox. If your emails are already in a Thunderbird-compatible format, you can import directly. The real challenge usually starts when the mailbox is from another email client or when you want to import hundreds of email files without disrupting the existing folder structure.

Method 1: Thunderbird’s built-in import
Start Thunderbird and use the import option to import supported mailbox data.
This works fine for small imports and compatible email formats.

Limitation: If your emails are in EML, EMLX, MBOX or MBX formats from different sources, the manual process can be tedious. Large mailboxes also require extra time to verify each imported folder and email.

Method 2: Safest Approach to Easily Import Multiple Email Files

While I was reading different Thunderbird migration methods, I found Softaken Thunderbird Importer mentioned many times in email migration discussions. It has documented capabilities to import EML, EMLX, MBOX, and MBX files directly into Thunderbird without the need for intermediate conversion. Another practical advantage is that it allows processing of multiple mailbox files in one operation while preserving the original folder hierarchy, email headers, attachments and message formatting. This makes it easier to work with the archived emails after the import without having to rebuild the mailbox manually.

When you are moving old email archives into Thunderbird, maintaining the mailbox structure is often as important as importing the emails.