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How to Copy, Move or Save Thunderbird Emails to Local Folder?

By Admin

Updated: March 17, 2026 ~ 5 Minutes Reading

Table of Contents
Summary: To save Thunderbird emails to local folders in bulk on Windows or Mac, you can simply create a new Local Folder in Thunderbird, and move or copy emails stored on IMAP server to that account.

There may be a few reasons why you want to move emails from IMAP mailboxes to local folders in Thunderbird, such as creating a local backup, freeing up server space, organising the mailbox data, and archiving data before deleting or removing an account in Thunderbird.

We have listed the step-by-step instructions to copy Thunderbird emails to the local folder and walk through to automatically move them to the local folder using Message filters.

 About Thunderbird Local Folders

When you save Thunderbird emails to a local folder, they are stored on your desktop in the MBOX format.

Here is the location of the local folder in the Thunderbird profile:

On Mac:
~/Library/Thunderbird/Profiles/xxxxxxxx.default-release/Mail/Local Folders/

On Windows:
C:\Users\YourUsername\AppData\Roaming\Thunderbird\Profiles\xxxxxxxx.default-release\Mail\Local Folders\

Linux:
~/.thunderbird/

There is no set limit on how many emails can be downloaded to the local folder in Thunderbird. Since they are saved in the C drive (or system storage), it depends on the available free space in that partition.

Important Note: If you move emails from IMAP to Thunderbird local folder and not copy them, they will be deleted from the IMAP server.

Manual Approach to Save Thunderbird Emails to Local Folder

Mozilla Thunderbird has a built-in option to move or copy an email to the local folder on all versions. Here are the steps to follow:

  1. Open Thunderbird and right-click on local folders.
  2. Select the New folder option and name it as per your preference (eg: MoveToLocal).
  3. Press Create Folder to confirm.
  4. Open the Mailbox as you want to copy emails.
  5. Select all emails using CTRL+A or CMD+A.
  6. Right-click on Selected emails.
  7. Choose Move To or Copy to as needed.
  8. Select the Local Folder >> newly created folder (MoveToLocal).
  9. Open the folder to verify if all Emails are successfully saved in Thunderbird’s local folder.
Tip: To copy all emails from a custom IMAP folder to a Local Folder at once, right-click on the folder, choose Move/Copy To, and choose the local folder as the saving destination. Does not work for pre-built folders like Inbox, Sent, Draft, and Junk.

Learn More: How to Archive Emails in Thunderbird Locally?

Automatic Setup to Move Thunderbird Mails to Local Folder

There is no direct and automatic way offered by Thunderbird to bulk save all emails to the local folder. However, you can set the Thunderbird message folder to move and copy them at once automatically.

Note: The message filter setup to download all Thunderbird emails to the local folder pre-assumes the maximum email size limit sent or received is 30 MB with an attachment.

Here are the steps to follow:

  1. Go to Menu >> Tools in Thunderbird.
  2. Select the Message Filter option.
  3. Click on the New option.
  4. Ensure the Getting New Mail box is checked.
  5. From the Filter attribute drop-down select Size(in kB), form operator choose is less than, and enter 30,000 in the value box.
  6. Choose the Copy To or Move To option from the Perform This Action drop-down.
  7. Choose the local folder where you want to save emails from IMAP accounts in Thunderbird.
  8. Press Ok and then press Run Now.
Wait for the process to be completed. It can be time-consuming. Since it depended on IMAP synchronization to carry out the process smoothly, you need a stable internet connection.

Why Saving Emails in Thunderbird Local Folders Is Not Enough?

Copying all Thunderbird emails to the local folder does not replace the need to back up Thunderbird profile data. Here is a restriction on downloading emails to the Thunderbird local folder for backup needs:

  • In case your Thunderbird profile gets corrupted, your saved emails in the Local Folder are also at risk.
  • Restricted by your system storage, and there is no option to move to an external storage device.
  • Emails will be saved only in MBOX format, which can be difficult to restore in other email clients like Outlook.
  • Also, it can be time-consuming, not suitable for bulk data, and often fails or leads to corruption.

Get Thunderbird Backup Tool to download Thunderbird emails locally onto your desktop or to copy Thunderbird emails to a flash drive into multiple formats like PDF, MBOX, EML, TXT, HTML, MSG.

Why Use a Tool?

  • No restriction on mailbox or profile size
  • Can download emails even if Thunderbird crashes.
  • Offers advanced filters such as date range, To/From, and directory.
  • You can even migrate Thunderbird emails to an IMAP server for cloud security.

Troubleshoot: Thunderbird Save Emails to Local Folder Not Working

Thunderbird often fails to copy all emails to the local folder at once. This can be due to:

  • Unstable internet connection
  • Bulk email reallocation
  • No free space on your computer

To save emails to Thunderbird local folder without issue, try:

  • Repairing Thunderbird folders
  • Freeing up disk space on your PC
  • Switch to a different connection
  • Use the safe mode to troubleshoot the issue

Learn to Fix: Thunderbird Local Folder Not Showing Error

FAQs: Thunderbird Move Emails to Local Folder

Q1: Can I read emails stored in the Thunderbird local folder on Android?
No, local folders are saved in your PC; thus, they are not synced with other devices.

Q2: Can I save IMAP or POP emails locally in Thunderbird?
Yes, you can simply select the email, right-click, and move or copy it to the local folder in Thunderbird.

Q3: Will I be able to access email saves in the Thunderbird local folder offline?
Yes, since they are saved on your desktop, you can view them offline in Thunderbird.