Import MBOX Emails to Microsoft 365?

Himanshu Goyal
Himanshu Goyal linkedin | Updated On - May 16, 2022 |

Read time 7 minutes

Many users nowadays use the desktop version of MS Office available with the Office 365/Microsoft 365 subscription. Unlike the stand-alone Office applications, it is subscription-based and not a one-time purchase. However, features and functions are somewhat the same as that of the latest version of the MS Office suite. Like other Office applications, MS Outlook is also available with this suite. And this Outlook Microsoft 365 is popular with many users because of the popularity of Office 365/Microsoft 365. After the subscription of Office 365, many users of the emails clients like Thunderbird are moving to Outlook Microsoft 365.

Do you want to access your MBOX emails with Microsoft 365 but not find the right tool that is reliable and easy to use?

Then don’t look anymore!

We have created this blog to help you understand how you can import MBOX to Microsoft 365.

Note for those who are not aware of Microsoft 365 Outlook – It is the Outlook app that you get with your Microsoft 365- subscription.

Now, let’s get back to the main topic.

MBOX is a file format that is used by many email clients like Mozilla Thunderbird, Eudora, Apple Mail, MS Outrage, PowerMail, and many more. But, when you cannot use the data in the same format (MBOX) with Microsoft 365 – you’ll either have to convert it to PST or import it directly to Microsoft 365.

Instant Solution

Try automated tool Kernel MBOX to Office 365, to migrate single/multiple files directly from MBOX/MBX/MBS to Office 365 in a single attempt.

Need to Import MBOX to Microsoft 365

Outlook Microsoft 365, like other Outlook versions, allows users to organize personal information like emails, contacts, calendars, tasks, and journals.

Outlook Microsoft 365 is a part of MS Office Suite, and those who purchase MS Office get a professional email client as a part of it. Generally, there is no need to import MBOX to Microsoft 365 unless you have trouble accessing your MBOX email client. However, Outlook Office 365 is more advanced than open-source email clients like Mozilla Thunderbird, which uses the MBOX format. Also, Outlook is compatible with Microsoft platforms like MS Exchange Server and Microsoft 365.

Read Also: While switching to Outlook Microsoft 365 from any MBOX email client, one essentially has to move their MBOX emails to Outlook.

How to Import MBOX to Microsoft 365?

The only manual method to import MBOX emails to Outlook Microsoft 365 is by converting it to a PST mailbox, and for that, you can refer to free methods to convert MBOX to PST. For example, if you have a Thunderbird account and MS Outlook on your system, then you can export the MBOX file to PST. Here’s how:

  1. Open Mozilla Thunderbird and select the folder that you want to migrate.
  2. Select all emails from that folder with Ctrl + A.
  3. Now, right-click on selected emails and click Save As > File.
  4. Save the file to a specific location.
  5. After saving the file close Mozilla Thunderbird and open MS Outlook.
  6. Create a New Folder and drag the saved file to this folder.

Thus, MBOX emails get saved in a PST mailbox.
The manual methods to import MBOX to Office 365 are very complicated. Also, they do not apply to every MBOX client, and you will be able to import only emails. Thus, you’ll have to use a third-party tool like Kernel MBOX to Office 365 that provides quick migration of MBOX mailboxes to Outlook Microsoft 365.

Drawbacks of Importing MBOX Into Office 365 using Manual Method

We know that the manual method can import MBOX files into Microsoft 365 mailboxes, but it has several drawbacks-

  • There is a need for no. of applications to be installed to migrate MBOX files from several machines to a single Office 365 which makes this process very lengthy
  • Using this method, we cannot migrate mailbox items such as contacts, calendars, tasks, and a lot more.
  • It requires technical knowledge and expertise to perform the process.
  • There is no guarantee of error-free results.
Kernel MBOX to Office 365

Designed with advanced algorithms, Kernel MBOX to Office 365 allows users to import MBOX data of more than 20 email clients to Microsoft 365 quickly without any hassle. Also, the smart filtering options help users to import only specific data based on their requirements. Let’s know this tool better with the working process.

  1. Install the software and launch it on your system.
  2. From the home screen of the software, click Select File in the top-left corner.Select MBOX file
  3. Add the specific MBOX file folder to the tool and click Finish.
    Add the specific MBOX file
    Note: You can select multiple MBOX files individually as well.
  4. You can see all the containing folders of the file; click any folder to preview its content.Preview of MBOX files and folder
  5. To save to PST file, click the Save button and select PST file (MS Outlook). Click Next.
    Select PST as a file saving option
    Note: If you want to save in your Microsoft 365 mailbox, select Office 365 from the given list, and click Next.
  6. Apply the filters to the files as per your requirements, such as item type, date, from, to, etc., and then click Next.Apply filter option
  7. Provide PST file splitting options as required. Click Next.
    Provide PST file splitting option
    Note: If you are saving in Microsoft 365, provide login details for the Microsoft 365 account in the next step and click Finish.
  8. Select Office 365 as a saving option

The MBOX file will be saved in a PST file (or Microsoft 365). You can now import the PST to Outlook Office 365.


Importing MBOX to Outlook Microsoft 365 can be daunting for new users, especially with the manual approaches, as they are complicated and not that reliable. In this article, we discussed how you could import MBOX files to Outlook Microsoft 365 quickly with the help of manual methods, as well as an automated solution Kernel MBOX to Office 365.

Kernel MBOX to Office 365