How to Import MBOX files to Gmail with All Emails and Attachments?

Published By Jamie Kaler

Approved By Rollins Duke

Published On January 9th, 2026

Reading Time 10 Min Read

Overview: A complete step-by-step guide on how to import MBOX files to Gmail with attachments, folder structure, and formatting. Multiple secure methods for Gmail users to restore, migrate, or import MBOX to Gmail with or without Thunderbird – using an advanced MBOX to Gmail Converter, based on your needs.

As per updated statistics of 2026, Gmail is used by over 1.8 billion users worldwide. Although it provides various advanced options, it does not offer a native way to import MBOX files directly.
Therefore, users need a dedicated tool like RecoveryTools MBOX to Gmail Wizard or email clients like Thunderbird to upload .mbox files to Gmail.

This guide lays out step-by-step methods to transfer MBOX files from any source to a Gmail account

Key Terms Related: MBOX to Gmail Import Process

MBOX/ .mbox is an abbreviation for Mailbox – an email file format. An MBOX file can store multiple emails with attachments, formatting details, and metadata. They can be exported from email clients like Thunderbird, Apple Mail, or Google Takeout.
Gmail is an email service offered by Google that allows users to access, read, and reply to their emails easily over the internet via a user-friendly Webmail Interface. However, you can not directly import MBOX to Gmail.
Thunderbird is a desktop email client for Windows & Mac. Users can add their Gmail account to Thunderbird using IMAP. Thunderbird allows users to import and export MBOX files in bulk using ImportExportNG. It can also be used to manually upload MBOX files to Gmail.

Can I Upload MBOX File to a Gmail Account?

Gmail does not offer a native way to import MBOX files directly. However, there are workarounds, such as email clients like Thunderbird, to transfer MBOX files into Gmail. Or use automated tools like MBOX to Gmail Importer to convert MBOX to Gmail with complete integrity without Thunderbird. This guide discusses both free-manual and professional methods in detail.

Why Users Import MBOX Files to Gmail Accounts?

Users import MBOX to Gmail for various reasons, from backup restoration, migration or centralized cloud access. Below are the most common situations where restoring MBOX emails to Gmail is required.

Migrating from Email Client: Users transfer emails from an when switching from an old email client, like Thunderbird, and have centralised access via Gmail webmail.
Restore Old Backup: Many users archive emails in MBOX format. In case of data loss or for accessing old emails, users may want to restore their old emails in Gmail.
Creating Cloud Backup: Importing your MBOX file into Gmail allows you to keep a backup of important emails, even if you stop using the original email client
Better Accessibility: Users can convert MBOX to Gmail to easily search and access old emails stored in the MBOX file within the familiar Gmail interface.
Save Space on PC: Uploading MBOX files to Gmail free up local storage by using Gmail’s 15 GB of free space, while also benefiting from spam filtering and powerful search features.

Important Considerations Before Importing

Since Gmail does not offer a native way to import MBOX files, choosing the right method is important. If you have a small number of emails, the manual method using Thunderbird can work seamlessly. However, for large mailboxes or professional use, a dedicated MBOX to Gmail converter is an expert-recommended choice, as it can handle bulk imports without limitations, avoid duplicates, preserve metadata, and attachments for compliance.

Method 1: Manually Import MBOX Files to Gmail Using Thunderbird

Using Mozilla Thunderbird is a free and widely used method for opening MBOX files in Gmail. It works well for limited amounts of data but can be technical, time-consuming, and prone to errors.

Prerequisites to Import MBOX to Gmail with Thunderbird

The latest version of Mozilla Thunderbird must be installed on your Mac or Windows device. Google stopped allowing less secure apps to connect to Gmail accounts on May 30, 2022.

To manually import MBOX to a Gmail account with Thunderbird, you must first install the ImportExportNG add-on. To install ImportExportNG in Thunderbird, open Thunderbird, click the hamburger menu in the top-right, select Add-ons and Themes, search for ImportExportNG, click Add, and restart Thunderbird.

This method is divided into three: we will connect a Gmail account in Thunderbird, import MBOX in Thunderbird, and then move the MBOX file items into the Gmail account. Follow both steps carefully:

Phase 1: Configure Gmail in Thunderbird

Open the Thunderbird application on your PC.
Click on the hamburger menu on the top right and select Account Settings.
Click on the New Account button and choose Mail Account from the drop-down menu.
Enter your full name and Gmail address. Press Continue.
Sign in to Thunderbird with Google.
Choose the IMAP option and press Continue.
Select the Gmail data that you want to import and finally hit Finish.

Phase 2: Import MBOX File to Local Folder of Thunderbird

Right-click on the Local Folder option below the configured Gmail account.
Select the ImportExportNG option, choose Import MBOX file, and then select the individual MBOX file you want to import.
Select the MBOX Files from the File Explorer or Finder. Press Open.

Step 3: Move Imported MBOX Emails to Gmail

Select the imported MBOX folder under Local Folders in Thunderbird.
Right-click on the folder or selected emails.
Choose Move To from the menu.
Select your Gmail account as the destination to import MBOX in Gmail with ease.

If you have multiple MBOX files to import into Gmail, select the All MBOX files from directory option during the import. After importing, move the emails from Thunderbird’s Local Folders to your Gmail account to transfer them in bulk.

If you want a direct method to upload an MBOX file to Gmail and do not want to get stuck in such a hectic method, then you can move towards the next solution.

Why Import MBOX Files to Gmail Without Thunderbird?

Before knowing the solution information, it is mandatory to understand why users should go for the paid solutions over manual methods. So that you can know which method will be best for you:

The manual method contains a risk of data loss, while the paid MBOX to Gmail converter tool migrates complete data without losing any single piece of information.
Multiple steps in the manual method takes long time, while expert solutions can import the MBOX file to the Gmail account directly in just a few minutes.
You need to install the Thunderbird application, while the mentioned MBOX to Gmail converter tool is an independent and standalone tool that doesn’t require the installation of any solution.

Method 2: Import MBOX File to Gmail without Thunderbird- Automatically

If you do not want to get stuck in a long and hectic method and you want a direct solution that does not waste your time, then you should use the automatic tools instead of the manual solution. Although there are many professional tools available in the market, you should use the RecoveryTools MBOX Converter only.

This tool is one of the best automated solutions to import MBOX files to Gmail without Thunderbird directly in bulk. This tool allows users to easily open an unlimited number of MBOX files to Gmail along with attachments, without any data loss.

Furthermore, the software can maintain the entire data structure, including email attributes and meta properties. Using this utility, you can import MBOX files to various saving 35+ options. Other capabilities are mentioned in the upcoming paragraph:

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Complete Steps to Use MBOX to Gmail Converter

Install this Converter on your Windows or Mac operating system.
Select MBOX files or folders to browse them directly on the panel using the “Select Files” and “Select Folders”.
After loading files, you get a smart “Preview option”. With this option, you can view MBOX files/folders.
Now, select “Gmail” as a saving option from “Select Saving Option”.
Hit on the “Filter Options” and apply the advanced filters to selectively import MBOX file to Gmail.
Enter the email address of your “Gmail” account here.
Press on the “Convert” button to continue the process.
Your default browser will open and select the needed Gmail account.
Grant the all required permissions using the “Select All” >> “Continue”.
The live process to import MBOX file to Gmail account will start.
After the successful process, a confirmation message will appear on the screen, and hit the “OK”.

Advanced Features of MBOX to Gmail Import Tool

Secure Conversion: Keep your data private and secure when uploading MBOX to Gmail with modern OAuth compliant with guidelines like HIPAA, CAPA & GDPR.
Bulk Import Made Simple: No need to manually set up Gmail using IMAP. The tool can seamlessly import multiple large MBOX files into Gmail.
Widely Compatible: RecoveryTools MBOX to Gmail Wizard can easily work on all standard Mac and Windows devices. You can import MBOX, MBX, MBS, and all other MBOX variants in Gmail with ease.
Import All Data: Accurately import MBOX emails, attachments, and metadata with formatting and folder structure preserved.
Selective Import: Advanced filter options of MBOX to Gmail Converter help you move only the required data based on Date, To/From, and subject. Saving Gmail storage space.
Multiple Language Support: Move MBOX email folder to Gmail in multiple languages, such as German, French, and many more.
24/7 Tech Support: If you need any help importing MBOX files to Gmail, you can simply connect with our dedicated team via Live Chat .
Auto Log Report Generation: Creates a log report with necessary details like Time Taken, Files Imported, and error logs. Making it easy for business and user handling bulk migration, easy to track and audit.

Similarly, the application can also be used to import an MBOX file to the Google Workspace account.

FAQs for Open MBOX Files in Gmail

Ques. Can I open an MBOX file directly in Gmail?
Ans: No, Gmail does not support opening large files directly. For this, you will need import MBOX to Gmail using RecoveryTools automated solution.

Ques. What are the limitations of the manual approach?
Ans: Requires additional tools/steps, potential data loss/formatting issues and large files can take time.

Ques. Which method should I choose and which method do experts recommend?
Ans: You should select the method for you by considering file size, technical expertise, budget and desired features. As far as the experts are concerned about which method they recommend, their direct answer is that they recommend the automatic tool.

Ques. Will I lose data during the manual import?
Ans: While unlikely, a slight risk of data loss/formatting issues exists.

Conclusion

In this article, we have mentioned a proper and effective solution to import MBOX file to Gmail with or without Thunderbird. In this article, we have used 2 best methods to do this import process, out of which you can use any one method as per your need.

Well, one of the best professional tools developed by the RecoveryTools expert team is mentioned here. There are many other utilities available on the internet, but we recommend that you stick with this tool and get the desired results. Furthermore, this device does not require any additional technical guidance to operate.