How to Convert MBOX to MHT / MHTML Quickly and Securely?

  Rollins Duke
Rollins Duke   
Published: January 7th, 2026 • 6 Min Read

Overview: This blog explains multiple free and professional ways to convert MBOX to MHT or MHTML with attachments. For users who need to save MBOX files in MHT format for legal tamper-free email archiving and easy access across multiple devices without an email client. Additionally, discover an advanced MBOX to MHTML converter for fast, bulk, and reliable conversion.

Understanding MBOX and MHT or MHTML File Formats

MBOX: MBOX or .mbox file format is short for Mailbox. It is a popular email format supported by many email clients like Thunderbird, Opera Mail, Apple Mail, Spicebird, and more. One MBOX file can store multiple emails with attachments preserved. However, they cannot be opened or accessed without an email client or a dedicated viewer.

MHT or MHTML: mht or .mhtml refers to MIME + HTML. It is a single-file archival format to save Email with attachments and formatting. One MHT or MHTML file stores a single email. They can be easily accessed through any device, simply via a web browser.

Due to this ease of access without an email client and formatting preservation, many people prefer to convert MBOX to MHT.

The guide lays out tried and tested ways by BitRecover experts to export MBOX data in MHT format with ease and best practices you should keep in mind for bulk conversion with complete integrity.

Reasons to Convert MBOX to MHT

  • MHT maintains the original email structure and attachments in a single file, which makes it easier to view the files without losing any data.
  • MBOX stores multiple emails in one huge file, whereas MHT saves each email separately, which helps in better management.
  • The files of MHT can be easily opened in web browsers. Therefore, they are more convenient to share without the need for an email client.
  • Converting huge MBOX files into separate MHT files keeps them secure and safe, prevents them from damage, and also organizes them simply.
  • MHT format is more suitable in case of storing the necessary and important emails, as it maintains and preserves formatting for the long term.

Manual Way to Convert MBOX to MHT

To convert MBOX to MHT, you need to follow these 3 stages. Follow the step-by-step guidance provided to you for saving the MBOX file to the MHT file:

Stage 1: Add Files to be Converted in Thunderbird

  1. Run the Mozilla Thunderbird application.
  2. Click on the hamburger menu on the top right and select the themes and add-ons option.
  3. Now, find ImportExportTools NG and download it.
  4. Right-click on the local folder and then choose ImportExportTools NG, and then import MBOX to Thunderbird.
  5. Now select the import types.

If you already have your MBOX data inside Thunderbolt, you can skip this step.

Stage 2: Download HTML From Thunderbird 

  1. Open Mozilla Thunderbird on your device.
  2. Choose the MBOX file folder that has emails, and then right-click on the folder and choose ImportExportTools NG, and then export all the messages in the HTML format.
  3. Now, you have completely saved your files in individual HTML file formats.

Stage 3: Convert Exported Files to MHT format

  1. Open an HTML file in a web browser and then open each HTML file in the browser.
  2. Now, do Ctrl+S, and you can successfully save HTML into MHTML.

Note: The option of  MHTML may also appear as a Web Page, Single File.

Drawbacks of Manual Ways 

  • Not a direct way to convert MBOX to MHTML.
  • Converting MBOX to MHT can be manually intensive, as you have to convert one by one.
  • There can be a risk of data loss when you use manual methods.
  • Time-consuming and error-prone for bulk MBOX to MHTML conversion.
  • Requires technical knowledge of file formats and webpages.

Expert Solution to Convert MBOX to MHT

BitRecover MBOX Converter Tool is one of the most intuitive and resilient software tools to export MBOX or .mbox file format into MHTML/ MHT and 29 other file formats for both Mac and Windows operating systems.

Further, the unparalleled uniqueness of this tool includes preserving the emails with attachments, including email text, images, and more

Most importantly, it is compatible with different email clients such as Gmail, Apple Mail, Thunderbird, and more. This tool enables users to filter the email data using subject lines containing phrases or specific keywords and data intervals. Now, let’s proceed to learn the steps of this robust software:-

Steps to Convert MBOX to MHTML Using Tool

  1. Launch the aforementioned tool in your Windows or Mac operating system.
  2. Now, click on “Select Files” and then Next.
    convert mbox to mht
  3. In the next pop-up window, choose the option for conversion while selecting the checkboxes > Next.
    select the required checkboxes
  4. Choose the MHT file format from the “Select Saving Option” and find out the location of the resultant file using the “Destination Path” option.
    choose the mht file format
  5. With this, to convert MBOX to MHT, select “Convert. 

Therefore, in a few steps, users can promptly convert the MBOX file. Also, this tool enables users to check the real-time update of the conversion of the data. And, once the process is completed, users can access the data in no time. Most importantly, there is no manual solution; therefore, using a professional tool is considered the optimal approach.

Features of Dedicated MBOX to MHT Converter

  • Bulk Processing Support: The converter optimizes the user’s work with a time-saving feature of bulk conversion in one go.
  • Intact Data Integrity: This utility secures email data like metadata, formatting, attachments, and much more.
  • Independent Utility: The converter works as an independent tool, as it doesn’t require any email client platforms for effective conversion.
  • Preserves Folder Hierarchy: The tool keeps the originality and the structure of the MBOX files for easy access.
  • File Naming Feature: It helps to manage the exported data with a customized name, like date, sender, and subject.

Conclusion

Overall, in this article, we have shed light on the reasons to convert MBOX to MHT / MHTML file extension. Since the accessibility of data using the MBOX file format is limited. Therefore, converting MBOX to MHTML/ MHT file format allows users to access and transmit emails, including images, text, video, and more.

As there is no free solution to directly convert the .mbox file to MHT format, using the above-mentioned tool is among the one-stop solutions and the professional preferred choice. 

Yet, if you have any queries left, feel free to reach out to BitRecover Technical Team directly via Live Chat. They are available 24×7. For error-free, quick, and reliable MBOX to MHTML conversion.


Live Chat