How to Import Outlook to Thunderbird - A Complete Guide

Mar 1, 2024 | By Deepak Singh Bisht

In this digital age, seamlessly migrating email data from one client to another is more than a convenience; it's a necessity. Whether for personal preference, organizational requirements, or the pursuit of better features, many users find themselves needing to switch. If you're considering moving your digital communication from Microsoft Outlook to Mozilla Thunderbird, you're about to embark on a journey that can be significantly smoother with the right guidance.

In this guide, we will serve as your roadmap through the Outlook to Thunderbird migration process, highlighting key strategies for a successful transition. We'll explore the essential steps to import Outlook to Thunderbird, focusing on both manual methods and the use of third-party Outlook to Thunderbird converter tools. If you are looking for a simple way to perform this conversion, then this guide will help you.

Why Import Outlook to Thunderbird?

In the realm of email management, the decision to import Outlook to Thunderbird is driven by a multitude of compelling reasons, making this migration a worthwhile endeavor for both personal and professional users. This section explores the benefits of making the switch.

Open-Source Flexibility: Thunderbird's open-source nature offers a level of customization and flexibility not found in proprietary software like Outlook. This allows for a wide range of add-ons and themes, enabling users to tailor their email experience.

Cost-Effective: Moving from Outlook to Thunderbird can be a cost-saving decision. Thunderbird is a free email client, which means you can access a robust set of features without the subscription fees associated with Microsoft Outlook.

Privacy and Security: Privacy-conscious users often prefer Thunderbird for its commitment to security, constant updates, and community-driven support system, ensuring secure and private communication.

Cross-Platform Compatibility: Thunderbird supports various operating systems, including Windows, macOS, and Linux, making it an ideal choice for users working across different platforms.

Easier Management of Multiple Accounts: Thunderbird excels at managing multiple email accounts seamlessly, offering features like a unified inbox and efficient account management.

Advanced Features: Despite being free, Thunderbird is packed with advanced features such as smart folders, message filtering, and tabbed email browsing, enhancing productivity and email management efficiency.

How to Import Outlook to Thunderbird?

The process of importing mail from Outlook to Thunderbird can be navigated through two main methods: utilizing manual techniques or employing a third-party Outlook to Thunderbird converter tool. Both approaches have their benefits and can be chosen based on your specific needs, technical comfort level, and the volume of data to be migrated. Let's delve into each method to understand how you can seamlessly perform the Outlook to Thunderbird migration.

Note: Before starting any migration method, it's crucial to prepare a backup of your Outlook data. This precaution ensures your information remains safe and recoverable should any unforeseen issues arise during the transition.

Instant Solution - SysCurve PST File Converter

| 312 Reviews

Quickly convert Outlook PST file to MBOX, EML, MSG, EMLX, HTML, and other file formats.

Method 1: Import Outlook to Thunderbird using the Default Program option

Transferring your email data from Microsoft Outlook to Mozilla Thunderbird may seem daunting, but the process becomes straightforward with the Default Program option. This method is especially useful for those looking to perform an Outlook to Thunderbird migration without additional software or converter tools. Follow this step-by-step guide:

Step 1: Set Outlook as the Default Email Client

  1. Open your computer's Settings by clicking on the Start menu and selecting the Settings gear icon.
  2. Navigate to "Apps" and then select "Default Apps" from the left sidebar.
  3. Scroll down to the Email section, click on it, and a list of available email applications will appear. Select "Outlook (Desktop)" as the default app.

Step 2: Import Outlook Emails to Thunderbird

  1. Launch Mozilla Thunderbird on your computer.
  2. Click on the Hamburger icon (three horizontal lines) and select the Tools option.
  3. Choose the Import option to access Thunderbird's import utility.
  4. In the import utility window, select "Import from Outlook" and click on the Continue button.
  5. Choose "Mail Messages" and click on Continue.
  6. Start the import process by clicking on the "Start Import" button.
  7. Finalize the process by clicking on the "Finish" button. Your Outlook data will now be accessible within Thunderbird.

By following these steps, you effectively import mail from Outlook to Thunderbird, leveraging the built-in capabilities of both applications. This method allows for a direct Outlook to Thunderbird migration, eliminating the need for external tools.

Method 2: Import Outlook to Thunderbird using Gmail IMAP

For users seeking a reliable method to transfer emails from Microsoft Outlook to Mozilla Thunderbird, Gmail's IMAP feature offers a versatile solution. This method uses Gmail as an intermediary for email transfer. Follow this detailed guide, which includes using Gmail's IMAP protocol and app-specific passwords for added security.

Step 1: Enable IMAP Protocol in Gmail

  1. Log into your Gmail account.
  2. Click on the Settings Gear icon at the top right corner and select See all "See all settings".
  3. Go to the "Forwarding and POP/IMAP" tab.
  4. Under "IMAP Access," select "Enable IMAP".
  5. Don't forget to click "Save Changes" at the bottom of the page.

Step 2: Generate App Password for Outlook and Thunderbird

  1. Visit
  2. Under the "Security" tab, find and enable 2-Step Verification.
  3. Return to the "Security" section, locate "App passwords", and select it.
  4. Enter "Outlook and Thunderbird" in the app name textbox, then click "Create".
  5. Copy the App password to a secure location and click "Done".

Step 3: Configure Gmail in Outlook

  1. Open MS Outlook on your computer.
  2. Go to File > Account Settings > Account Settings.
  3. Under the Email tab, click "New".
  4. Enter your Name, Gmail address, and the app password, then click "Next".
  5. Once verified, click "Finish".

Step 4: Migrate Emails from Outlook to Gmail

  1. In Outlook, navigate to the Gmail mailbox.
  2. Right-click on the Gmail mailbox, choose "New Folder", and name it.
  3. Select the emails to migrate from Outlook.
  4. Press Ctrl and drag these emails to the new folder within your Gmail account.
  5. Refresh your Gmail to see the emails in the new folder.

Step 5: Configure Gmail in Thunderbird

  1. Launch Mozilla Thunderbird.
  2. Go to "Account Settings" from the Menu.
  3. Click "Account Actions" at the bottom left, then "Add Mail Account".
  4. Enter your Name, Gmail Address, and App password. Ensure "Remember password" is checked, then click "Continue".
  5. Select "IMAP" from the "Available Configurations" and finalize by clicking "Done".
  6. A confirmation will display, signifying the successful addition of your Gmail account.
  7. Navigate to your Gmail mailbox within Thunderbird. Thunderbird will begin to download all the emails, including those you migrated from Outlook.

By following these steps, Gmail acts as a bridge to import mail from Outlook to Thunderbird, offering a straightforward migration process for those preferring not to use direct converter tools.

Method 3: Convert and Export Outlook to Thunderbird using an Outlook to Thunderbird Converter

For a direct and efficient solution to export emails from Microsoft Outlook to Mozilla Thunderbird, consider using a dedicated Outlook to Thunderbird converter tool. Tools like SysCurve PST File Converter tool streamline the process by converting Outlook's PST files into Thunderbird's MBOX format. This method suits users seeking a fast and reliable way to export their emails without manual steps.

  1. Download and install the SysCurve PST File Converter tool.
  2. After the installation, open the tool.
  3. Click on the "Add file" option within the tool's interface to browse and select the PST file you intend to convert. Confirm your selection by clicking on the "OK" button.
  4. The software will load the PST file and display its contents in a preview mode.
  5. Choose the "Export" option and then select the specific folders within the PST file that you wish to convert to Thunderbird's format.
  6. From the available format options, select "MBOX" as the export format. This is the file format used by Thunderbird for storing emails.
  7. Specify a destination path where you want the converted MBOX files to be saved.
  8. Click on the "Export" button to begin converting the selected PST file into MBOX format.
  9. Once the conversion process is successfully completed, the tool will display a notification. Click on the "Finish" button to conclude the process.

By following these steps, you can efficiently convert and export your Outlook data to Thunderbird, making the Outlook to Thunderbird migration process seamless and straightforward. The SysCurve PST File Converter tool provides a hassle-free way to transition between email clients without losing any of your valuable email data.

Other Helpful Features

  • Convert Outlook PST file to MBOX, EML, MSG, HTML, and other file formats.
  • Preview all PST file data.
  • Process unlimited PST files.
  • Accommodate PST files of any size.
  • Preserve the original structure of folders.
  • Migrate PST to Office 365 and Live Exchange server.
  • Free Outlook to Thunderbird conversion of the first 20 items from each folder.
  • Support all versions of MS Outlook, including Outlook 2019 and 2016.
  • Compatible with Windows OS, including Windows 10, 8, and 7.

Frequently Asked Questions

What is the best way to perform an Outlook to Thunderbird migration?

The best method depends on several factors including your personal preferences, the amount of data you need to transfer, and your technical expertise. You can choose from manual methods, utilizing Gmail IMAP as an intermediary stage, or opt for a more straightforward solution by using a dedicated Outlook to Thunderbird converter tool, such as the SysCurve PST File Converter, which offers a direct and hassle-free migration path.

Can I directly import Outlook PST files into Thunderbird?

Direct import of PST files into Thunderbird is not supported natively. To import Outlook to Thunderbird, you can use a third-party converter tool that can convert PST files into the MBOX format, which is compatible with Thunderbird, thus enabling a direct import process.

Is it possible to preview PST file data before converting?

Yes, with advanced tools like the SysCurve Outlook to Thunderbird Converter, users have the capability to preview all data contained within PST files prior to initiating the conversion process. This ensures that you convert and export precisely the data you require.

Can large-size PST files be converted for Thunderbird?

Absolutely. The SysCurve Outlook to Thunderbird converter tool is engineered to handle PST files of any size, ensuring the conversion of large email databases can be done smoothly and without complications.

Is there a free option for Outlook to Thunderbird conversion?

While there is no completely free tool available for this purpose, the SysCurve Outlook to Thunderbird converter tool offers a free demo version. This demo allows users to preview PST file emails and export the first 20 items from each folder, providing an opportunity to evaluate the tool's functionality and results before making a purchase.

Are my emails secure during the conversion process using this tool?

The SysCurve Outlook to Thunderbird converter tool employs advanced algorithms designed to prioritize security, ensuring that personal or sensitive information remains protected throughout the conversion process. As a desktop application, it keeps all converted data within your system, further safeguarding your privacy.

Does this tool require Outlook to be installed to perform the conversion?

No, the SysCurve Outlook to Thunderbird converter software does not require Outlook to be installed on your computer for accessing and converting PST files. It operates independently, allowing for PST file conversion without the need for Outlook installation.

Can I also transfer my contacts and calendar entries from Outlook to Thunderbird?

Yes, in addition to email conversion, the SysCurve tool also supports the transfer of contacts and calendar entries from Outlook to Thunderbird, ensuring a comprehensive migration of all essential data.

The Final Word

Embarking on the journey from Microsoft Outlook to Mozilla Thunderbird represents not just a transition between email clients, but a step towards embracing open-source flexibility, enhanced privacy, and a more tailored email management experience. This comprehensive guide has aimed to illuminate the path through the intricate process of migrating from Outlook to Thunderbird, ensuring that you are well-equipped to make this transition as smooth and efficient as possible.

Whether you choose to manually import mail from Outlook to Thunderbird, leverage Gmail's IMAP functionality as a bridge, or utilize a specialized Outlook to Thunderbird converter tool, the goal remains the same: to securely and accurately transfer your valuable data to Thunderbird. Tools like SysCurve PST File Converter stand out for their ability to directly export Outlook to Thunderbird, converting PST files into Thunderbird-compatible MBOX format, thereby simplifying what could otherwise be a daunting task.

The decision to migrate is often driven by the desire for a more flexible, secure, and cost-effective email management solution. Thunderbird, with its open-source nature, cross-platform compatibility, and robust feature set, offers an attractive alternative to Outlook's proprietary system. By following the methods outlined in this guide, you can ensure a successful Outlook to Thunderbird migration, preserving the integrity of your email data and adapting to a new client that better fits your needs and preferences.

Remember, the key to a smooth migration lies in careful preparation and choosing the right method for your specific situation. Whether you're a personal user seeking to streamline your email management or a professional looking to enhance your organization's communication tools, the transition from Outlook to Thunderbird can mark the beginning of a more efficient and satisfying email experience.

The Author

Deepak Singh Bisht

Deepak Singh Bisht

Content Lead |

Deepak Singh Bisht is a dedicated IT professional with over 9 years of experience, is a key member at SysCurve Software for the last 5 years. His expertise lies in email migration and data recovery, with a focus on technologies like MS Outlook and Office 365. Deepak, who also delves into front-end technology and software development, holds a Bachelor's degree in Computer Applications.

More from Deepak Singh Bisht