Home  »  PST Converter  »  How to Import Outlook to Thunderbird on Mac – Complete Guide

How to Import Outlook to Thunderbird on Mac – Complete Guide

Summary: Thunderbird is a free, open-source email client that receives continuous community-driven updates and improvements. Thus, it grows day by day, which makes Thunderbird the best email solution for users. On the other hand, MS Outlook is a very heavy & slow email client with lots of wanted and unwanted OST & PST files. Therefore, this blog will cover all the top secure methods to import Outlook to Thunderbird briefly. Plus, we will discuss how PST Converter can help in the bulk conversion of your Outlook data to Thunderbird..

 

Download Now Purchase Now

Query: How can I export Outlook to Thunderbird/MBOX format? I need to open these messages in another email application and want to avoid any data loss during the conversion.

Solution: Follow the steps below: 

  1. Install and run the tool.
  2. Select PST files or folders.
  3. Preview selected emails.
  4. Choose MBOX format or Thunderbird.
  5. Set destination path.
  6. Click Convert.

Why do Users Import Outlook Emails to Thunderbird?

Users often switch from Outlook to Thunderbird because of its lightweight nature and its being a cost-free way to communicate. Let’s discuss how this conversion comes to the advantage of the users.

Advantage The Thunderbird Edge
Cost & Freedom Completely free & open-source (no subscriptions!)
Performance Lightweight & fast, even on older computers
Privacy & Control Your data stays yours – no tracking or telemetry
Reliability More stable file format, avoiding PST corruption
Flexibility Highly customizable with themes & add-ons
Platform Support Flawlessly works across Windows, Mac, & Linux

These are a few reasons why users tend to import Outlook Data Files into Thunderbird. However, both the email clients (Outlook & Thunderbird) are powerful tools for business communications.

How to Import Outlook to Thunderbird?

There is no direct drag & drop way to move your Outlook data to Thunderbird email. There are 04 most secure ways to export your data:

  1. With Outlook Installed
  2. IMAP Method
  3. With Thunderbird’s Extension
  4. CloudXena’s Solution (Recommended)

Way 01. Outlook to Thunderbird Email Migration With Outlook

Here, users need to configure Outlook, and then we will move one by one to Thunderbird. We will divide this technique into two phases, and follow the step-by-step guide

Phase 01: Set MS Outlook as Default

  1. First, navigate in your system to Control Panel > Default Programs.
  2. Post that, set Microsoft Outlook as your default email application.

Step 2: Import into Thunderbird

  1. Then, open Thunderbird and go to Tools > Import.
  2. After that, select Mail and then choose Outlook.
  3. Lastly, click Next to begin the transfer.

Note: This method directly migrates your emails, calendar, and contacts. However, users have to move one by one only.

Now, you have successfully moved your MS Outlook emails to Mozella Thunderbirds directly. Although this workaround comes with a few challenges:

Challenges: Convert Outlook to Thunderbird via Outlook

  • Requires Outlook installed & configured.
  • Moreover, it may not transfer all data types.
  • One-time migration only (no sync).
  • Plus, there is a risk of data corruption/duplicates.
  • No filtering or selective import options.
  • Additionally, users have limited control over the process.

Way 02. Move Outlook Emails to Thunderbird with IMAP

Here, we will use Gmail’s IMAP service as an intermediary bridge to transfer emails from Outlook to Thunderbird. This is one of the best free methods when Outlook is not installed in your system.

  1. Log in to your Gmail account and enable IMAP access.
  2. To enable go to, Settings → See all settings → Forwarding and POP/IMAP.
  3. After that, configure your Gmail account in Outlook (if accessible).
  4. Next, drag and drop emails or folders from your PST file into your Gmail folders.

    5. This will sync and upload them to Gmail’s servers.

  5. Then, add the same Gmail account in Thunderbird using the same IMAP settings.
  6. Lastly, Thunderbird will automatically synchronize and display all the emails you uploaded.

With this method, users have easily forwarded their MS Outlook Data to Thunderbird. However, this IMAP process has a few limitations:

Limitations: Import Outlook to Thunderbird via IMAP

  • Limited by Gmail storage space
  • Slow transfer speed (internet-dependent)
  • Risk of sync issues & lost folders
  • Manual folder-by-folder upload
  • Requires Outlook access initially

Way 03. Convert Outlook to Thunderbird with ImportExportTools NG Add-on

This method is ideal if you have already convert PST to MBOX. The ImportExportTools NG add-on provides powerful tools to import the MBOX file directly into a Thunderbird folder.

Phase 01. Install the Add-on:

  1. Open Thunderbird and go to the Add-ons Manager.
  2. Then, search for ImportExportTools NG.
  3. Click Add to Thunderbird and install it, restarting Thunderbird when prompted.

Phase 02. Import the MBOX File:

  1. In Thunderbird, right-click on the local folder (e.g., Local Folders) where you want to import the emails.
  2. From the context menu, navigate to ImportExportTools NG.
  3. Next, select Import MBOX File.
  4. In the dialog box, choose the option Import directly one or more MBOX files and click OK.
  5. Finally, browse to and select your converted MBOX file to begin the import.

While ImportExportTools NG is effective for direct import, it has key limitations.

This method imports all emails into a single folder, losing Outlook’s original folder structure. Restoring the organization requires manually recreating folders and importing them separately, which is time-consuming. Large imports can also create significant clutter.

Way 04. Import Outlook to Thunderbird Professionally

When the above method does not work properly, we recommend the CloudXena PST Converter tool. It is a specialized email migration tool that expertly converts Outlook PST files into versatile formats like MBOX, EML, and PDF. It ensures a seamless transition by preserving original folder hierarchies, metadata, and data integrity. Ideal for migration, backup, or archiving, it offers secure, bulk conversion capabilities for reliable email management.

Steps to Import Outlook Emails to Thunderbird Windows 10

  1. Install & Launch the tool as Administrator
  2. Next, choose the Single/Multiple Files or Folder option.
  3. After that, browse & add your PST files (Outlook Data).
  4. Thereafter, Preview & Select emails from the folder tree.
  5. Post that, choose Thunderbird as the output format.
  6. Further, put the Thunderbird credentials to be converted.
  7. Subsequently, set the Destination folder path.
  8. Lastly, click convert to start the process.

With CloudXena’s Ultimate PST converter, you can import Outlook emails to Thunderbird Mac/Windows easily.

Why Import Outlook to Thunderbird with CloudXena?

  • Accurate PST to MBOX Conversion
  • Maintains Folder Hierarchy
  • Supports Bulk Migration
  • No Outlook Required
  • High-Speed Processing
  • Cross-Platform Support
  • Secure and Reliable

Reading Suggestion: How to Convert PST to TIFF File Format?

Author’s Note:

It unlocks a faster, more flexible email experience to Import Outlook to Thunderbird, but manual methods often risk data loss and structural chaos. For an easy, hassle-free transition, specialized tools like CloudXena PST Converter eliminate these hurdles.

This professional solution preserves every folder and attachment with precision through a secure one-click process. Enjoy Thunderbird’s advantages immediately with guaranteed data integrity and zero migration stress.

Frequently Asked Questions

Q1. Can I import my Outlook emails to Thunderbird without using any third-party software?

Ans. Yes, but with significant limitations. You can use Thunderbird’s built-in import function if Outlook is installed and set as your default mail client. Alternatively, you can use an IMAP server (like Gmail) as an intermediary. However, these manual methods are often slow, risk data loss, do not preserve folder structures well, and can be technically complex for large mailboxes.

Q2. Why should I use CloudXena PST Converter instead of a free method?

Ans. While free methods exist, CloudXena PST Converter is designed for a reliable and complete migration. It guarantees that your original folder hierarchy, all email metadata, and attachments are preserved perfectly. It works without needing Outlook installed, supports bulk conversion for large mailboxes, and completes the process quickly and securely, saving you time and preventing potential data loss.

About The Author:

I, Simran Bhatia am a Technical Content Writer specializing in data management, email migration, and data recovery IT solutions. My focus is on simplifying complex processes into clear, practical guides that combine technical accuracy with real-world value for IT admins, decision-makers, and everyday users. For me, writing is not just about explaining technology, it’s about making it accessible, reliable, and valuable for readers.

Related Post

Convert PST to TIFF
How to Convert PST to TIFF File Format? Quick Solutions
Convert PST to MBOX
How to Convert PST to MBOX Format? Quick Solutions
Comprehensive Guide to Convert PST to MSG Format