How to Import PST to Thunderbird? [2025]

Jackson Strong | November 11th, 2025 | Mozilla Thunderbird

This write-up will guide you on how to import PST to Thunderbird without any data loss. Here, we are going to explain the two best methods to open PST file in Thunderbird. This post will show you every detail related to the Thunderbird import PST process. So, let’s continue with us to know everything in detail.

PST is a file format used by MS Outlook to store its mailbox data, including emails, contacts, calendars, and more. However, there are times when users want to import PST file in Thunderbird for various reasons such as;

  • Thunderbird is a free and open-source email client.
  • Simple and easy-to-use interface.
  • Open PST file without Outlook installation.
  • Manage multiple email accounts in one Thunderbird profile.
  • Switch from Outlook email client to Thunderbird.

Can Thunderbird import PST? No, Thunderbird doesn’t support PST file directly. Fortunately, with the right methods and tools, you can successfully convert PST to Thunderbird without losing important messages.

How to Open PST File in Thunderbird Manually?

You can’t directly import PST to Thunderbird. First of all, import PST file in MS Outlook via the Import/Export Option. After that, follow the step-by-step guide below to import emails from Outlook to Thunderbird.

  1. Open the Control Panel and navigate to Programs>>Default Programs>>Set your default programs.
    open pst in thunderbird
  2. Select Outlook, click Set this program as default and hit OK.
    import pst in thunderbird
  3. Open Thunderbird and click the Thunderbird menu.
    import pst in thunderbird
  4. Go to Tools>>Import.
    import pst file in thunderbird
  5. Choose Mail and click Next.
    import Outlook data in thunderbird
  6. Choose Outlook and click Next.
    open pst in thunderbird
  7. Click Finish and let Thunderbird import Outlook PST data.

Please Note: This solution may not work in Thunderbird 115 edition. Also, it requires full version of MS Outlook installation. This is because in trial edition of MS Outlook, import export feature will not work.

How to Import PST to Thunderbird Without Outlook?

Download and install the Advik PST File Converter on your Windows computer. It allows you to transfer emails from .pst file to the Thunderbird client. Not a single bit of information or message will be lost during the data transfer. You can even batch convert PST to Thunderbird effortlessly. The software will also maintain folder and sub-folder structure and email attributes as well. Thus, no data loss or modification would take place.

Click on the FREE download button and analyze its working process at no cost.

Note: The demo version will let you import 25 emails from each folder.

Steps to Import PST File into Thunderbird Profile

Step 1. Launch software on your Windows PC.

run the software

Step 2. Click Select File(s) and add .pst file.

select pst files

Step 3. Choose Thunderbird as a saving option.

Choose Thunderbird as a saving option

Step 4. Click Convert and analyze the process.

click convert to import pst to thunderbird

Now, sit back and relax! The software will start copying emails from PST to Thunderbird.

Watch How Thunderbird Import PST Without Outlook

Why Choose Automated Software?

The software will also help in other scenarios as well. Below are a few highlights of the software.

  • Bulk Import PST Files: This tool has a dual mode, which allows you to import PST files into Thunderbird in bulk.
  • Direct Importing: This is a standalone application. With this software, you can import .pst file into Thunderbird without Outlook.
  • No Size Restrictions:  The software can import PST in Thunderbird without any size limit. You can easily open large PST files.
  • User-Defined Location to Store Data: You can choose any location on your system to save the output files, or it will default to the desktop.
  • 30+ Saving Options: The software supports various options to transfer or convert PST files. Such as that you can import PST to IMAP, Gmail, Outlook.com, O365, Zoho Mail, Yandex Mail, and many more.
  • Easy-to-Use GUI: The software interface of this PST to Thunderbird Converter software is very simple and user-friendly. And it ensures 100% data accuracy as well.
  • Windows Compatibility: This utility works with all Windows versions, including Windows 7, 8, 10, 11, and both 32-bit and 64-bit systems.

Final Ending

In this post, we have discussed how to import PST to Thunderbird. After knowing the fact that Mozilla Thunderbird does not have the option to import PST files, we found a loophole. The manual trick is 100% workable in the older version of Thunderbird. It may or may not work in the latest edition due to various technical changes. If it does, then it’s great. If it doesn’t, you can opt for the professional automated software. You will be able to save your manual efforts and time and get the results accurately.

Frequently Asked Questions

Q 1. How do I import PST file into Thunderbird 91?

Ans. Yes, you can transfer your PST file into Thunderbird 91 or any other version by following the manual or automated steps mentioned above.

Q 2. Will this software work to import PST file to Thunderbird on Windows 11?

Ans. Yes, this application works on all Windows versions, including Windows 11.

Q 3. How can I test the software before purchasing it?

Ans. You can take a trial of the PST to Thunderbird converter free, which allows you to transfer 25 PST emails into a Thunderbird profile. If satisfied, you can purchase the full version for complete migration.

Q4. Can Thunderbird import PST file directly?

Ans. No, Thunderbird can’t import PST files directly. You’ll need to use automated software or convert PST to MBOX which is a compatible format of Thunderbird.

Q5. Will my attachments be maintained in the PST file during conversion?

Ans. Yes, the automated software retains attachments and all other key elements of your PST emails while transferring into Thunderbird.