Exporting Thunderbird email helps you move messages, contacts, and settings to another client or a fresh computer without losing data. This guide explains the main methods, what to expect, and how to avoid common pitfalls when you export Thunderbird email.
Whatever your reason for migration, understanding file formats and backup options makes the process smoother. The summary below highlights the most important choices before you start the export.
| Method | Best For | File Created | Compatibility |
|---|---|---|---|
| ImportExportTools NG Add-on | Single folders or entire accounts | MBOX file | Thunderbird, Apple Mail, Thunderbird clones |
| Manual profile copy | Full profile backup including settings | Profile folder copy | Same Thunderbird version on same OS |
| IMAP sync to new provider | Cloud access and recent messages | Server copy, optional local export | Any client supporting IMAP |
| Address Book (CSV) export | Contacts migration only | CSV file | Most mail clients and services |
Using ImportExportTools NG to export Thunderbird email safely
Install ImportExportTools NG from the Firefox Add-ons store to gain fine-grained control over what you move. This add-on lets you export Thunderbird email folder by folder while preserving the original structure, which reduces the risk of missing messages or broken threads.
Before you run the export, close Thunderbird and back up your profile folder so you can recover if anything goes wrong. The tool writes MBOX files, a widely supported format that keeps headers, attachments, and encoding intact for later import into other systems.
After export, verify a few sample files on another machine or client to confirm formatting and attachments work as expected. This step helps you avoid surprises when you switch to a new email platform or restore data after a failure.
Export Thunderbird email via IMAP for cloud access
Connecting Thunderbird to an IMAP server and enabling folder sync can act as a live export without creating local files. Your messages stay on the server, and you can access them from any device that supports IMAP while Thunderbird continues to synchronize in the background.
If you plan to retire the local profile, copy the data to a cloud account first and then use the provider’s web interface to download a complete archive. Check provider storage limits and export options, because policies and quotas can restrict how much you can move at once.
Keep a local copy until you confirm that the cloud archive is complete. This dual safety net protects you against sync errors, accidental deletions, or unexpected service changes while you learn how to export Thunderbird email the way your workflow needs.
Exporting contacts and address books from Thunderbird
Your address book is just as important as your messages, so include it in every migration plan. Thunderbird stores contacts in a dedicated global address book or card files, which you can export directly to CSV for reuse in other tools.
Open the address book, select the directory or card, and choose export to save each group as a separate CSV file. Note custom fields or photos, because standard CSV export may not include them, and plan for a little manual cleanup after you move the data.
Key steps to export Thunderbird email reliably
- Back up your entire profile folder before starting any export
- Test ImportExportTools NG on a small folder first to confirm output quality
- Prefer MBOX or EML formats for broad compatibility with other clients
- Verify size and naming rules of your target platform before bulk upload
- Keep a local copy until you confirm the new environment works correctly
- Document steps and settings so you can repeat or troubleshoot the process later
FAQ
Reader questions
Will exporting Thunderbird email as MBOX keep my folder structure intact?
Yes, ImportExportTools NG preserves the folder hierarchy in separate MBOX files or a combined file depending on your choice, making it easier to map old structure to the new client.
Can I export Thunderbird email to PST for Outlook?
direct Thunderbird to PST is not supported, so the recommended path is to export to MBOX or EML and then use a reliable third‑party converter that creates PST for Outlook import.
What should I do if some messages fail during the export?
Log the error details, skip the problematic messages temporarily, and retry after checking for corrupt messages or oversized attachments. In some cases, splitting the export into smaller batches avoids timeouts or file size limits.
Is it safe to copy the Thunderbird profile folder instead of using an export tool?
Copying the profile folder is safe for migrating to another computer with the same operating system and Thunderbird version, but it may not work across platforms or after major updates. Use profile copy for short-term backup and prefer file-level exports for long-term migration.