How to Import MBOX to IMAP Server: A Step-by-Step Guide

  Rollins Duke
Rollins Duke   
Published: May 15th, 2025 • 7 Min Read

In this post, we will find multiple ways to import MBOX to IMAP server, including a step-by-step guide. Also, we offer you both manual and automated solutions to easily upload MBOX to IMAP server without facing any problems. Stay tuned with us and learn more important information after reading this article.

Understanding of MBOX and IMAP Individually

Before directly exploring the methods, it is necessary to understand what these formats contain and why the migration is important.

MBOX is a popular and widely used email storage format that stores multiple emails in a single file and is supported by a variety of email clients such as Thunderbird, Apple Mail, Eudora, and Postbox. It stores emails in a plain text file, which makes it easy to share across various platforms. Also, it stores attachments separately without any alteration. The MBOX format’s main purpose is to store emails locally, facilitating easy backups and archiving of emails.

IMAP stands for Internet Message Access Protocol, which is an email retrieval protocol that allows users to access and manage emails directly from the mail server. It keeps all the emails on the email server, further enabling users to access their email messages from multiple devices without downloading them locally. It offers better email management and security, and reduces local storage usage by making it cloud-friendly.

After understanding the differences, let’s get into the reasons why users prefer IMAP over keeping data in an MBOX format.

Reasons to Upload MBOX Files to IMAP Server Account

  • Multiple Device Access – MBOX stores files locally, which means they can access those files only on the device where they are stored. Whereas IMAP saves emails on the mail server, which allows users to access them from multiple devices such as computers, smartphones, and tablets.
  • Real-time Synchronisation Takes Place – With IMAP, any changes made will be synchronised automatically across all devices, ensuring up-to-date content. On the other hand, changes made in MBOX would not be reflected across devices.
  • Better Email Management – IMAP allows users to organise and manage emails into folders, whereas MBOX stores emails in a single file, which makes it harder for users to manage and search for a specific email.
  • Email Size Limitations – IMAP imposes no file restrictions as emails are stored directly on the server. Unlike MBOX, emails are stored locally and can be large, requiring more storage space.
  • Backup and Data Security – Since MBOX files are stored on the local system, chances of data loss can take place if the device fails or gets damaged, so backup is important. Whereas, in IMAP, the emails are secured and can be accessed easily even after device failure.

Now, in the section below, we will discuss how you can manually import MBOX to IMAP server. Follow the steps as explained for effective results.

How to Import MBOX to IMAP Server Account Manually?

We will mention steps for both Mac & Windows machines using third-party applications like Thunderbird for Windows and Apple Mail for macOS. Both applications support MBOX data files and allow you to set up IMAP-based email services. So, you can easily import MBOX to IMAP server by following the given steps:

Method 1: Use Thunderbird for Windows OS

This method is divided into two steps to upload MBOX to IMAP server in bulk. Firstly, we will import MBOX files to Thunderbird account, and then we will connect IMAP account here.

  1. Start your Thunderbird profile.
  2. Select the “Tools” >> “ImportExportTools NG” >> “Import MBOX Files” from the appearing list.
  3. After that, find the “Import One or More MBOX Files” option and select it.
  4. Locate the destination of your MBOX file and choose “Open”.
  5. And you can analyse your MBOX file under other folders.

Step 2: Connect IMAP-based Email Service

  1. Restart your account.
  2. Click on the “Menu” >> “Account Settings” from the list.
  3. And then find “Account Action” >> “Add Mail Account”
  4. Enter the IMAP account credentials.
  5. Select the IMAP server details and hit the “Continue”
  6. Lastly, click on the “Finish” icon to import MBOX to IMAP server.

And successfully IMAP server account connected. Now, head to the uploaded MBOX file in your Thunderbird profile, right-click on it using the cursor, choose the “Move to” option, and select the connected IMAP account.

Method 2: Import MBOX to IMAP Server for Mac OS

  1. Open Apple Mail, go to “Mail” >> “Add Account” and add your IMAP account by entering the required details.
  2. Click “File” >> “Import Mailboxes” and select MBOX files, and then click “Continue”.
  3. Select MBOX files and click “Choose” to import them.
  4. After MBOX files are imported into Apple Mail, select emails and drag and drop them into the folder under your IMAP account.
  5. At last, when your emails get transferred, they will be automatically synced with your IMAP server. Verify it by checking the IMAP folder on another device.

Limitations of All Manual Methods

  • Manual methods require a lot of time in moving individual emails into an IMAP account, especially when dealing with large files.
  • It does not offer a bulk export option; users have to transfer files one by one.
  • Increases the risk of data loss and corruption.
  • Requires more human effort and may not upload attachments properly; formatting issues may occur.

Alternate and Direct Method to Import MBOX to IMAP Server Account

In this section, we will discover how to upload MBOX to IMAP server seamlessly without compromising a bit of data, using an automated solution. The BitRecover MBOX Converter is a standalone software that supports 35+ formats, email clients, and servers, providing cross-platform compatibility.

It opens a wide path for users to import MBOX to IMAP server as per their choice. Additionally, to perform migration, users do not require any specific technical knowledge; they can simply follow the steps mentioned below.

MBOX to IMAP Converter – Step Guide

  1. Download, install, and launch the MBOX to IMAP Importer Tool.

    MBOX to IMAP Importer Tool

  2. Add MBOX files or folders for conversion and click Next.

    Add MBOX files

  3. After that, select “IMAP” as the saving option from the list of output formats.

    saving option

  4. Now, enter your IMAP account email address and password to import MBOX to IMAP server.

    IMAP account email address

  5. At last, click “Convert” to start the conversion process.

    import mbox to imap server

Why Alternate Tool Over Manual Methods?

  • All-in-one MBOX to IMAP importer is an expert-trusted and robust solution that ensures fast and quick conversion without data loss.
  • The software allows users to import MBOX to IMAP server accounts directly without requiring the help of any other email client.
  • Convert MBOX files in bulk and in a single cycle, saving users valuable time and effort.
  • Preserve original file formatting, email headers, and folder hierarchy throughout the conversion process.
  • It is compatible with all versions of Windows and macOS, including the latest and older editions.
  • Capable of performing large-scale file migration with attachments, as it does not impose any file size limitation.

Final Words

In conclusion, I would conclude that to enjoy a hassle-free process to import MBOX to IMAP server, use the professional solution. As it not only provides a smooth transition but also guarantees preserving data integrity, metadata, and attachments during the whole conversion process.

For your further satisfaction, it offers a free trial version to test the workings of the software. You can utilise it fully and, to get more benefit, purchase its license key. Moreover, if you still face any issues, you can contact our support team, available 24/7.

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