How To Convert OST to MBox

Our flagship Total Outlook Converter program is famous for the amount of non-email output formats it can handle when it comes to extracting your data. PDF, TIFF, DOC, XHTML and JPEG are all supported, in addition to numerous other formats.

Quick answer: To convert OST to MBox, install Total Outlook Converter, let it locate your OST file, select the folders and emails you want, click the MBox button, choose the output fields and attachment options, then click Start. It reads OST directly and exports thousands of messages in bulk to MBox files that Thunderbird, Apple Mail, and SeaMonkey open natively — processed offline on your PC.

What a lot of people do not realise is that it is equally effective when it comes to migrating between mailboxes - for example, if you need to convert OST to MBox. These days, of course, it is all too common for people to have multiple mailboxes, even within their company accounts.

If you need to migrate OST to MBox then you are probably talking about dealing with thousands of files so the need for a dedicated tool that can handle bulk processing is essential.

In addition to helping you export OST to MBox format, Total Outlook Converter also boasts a wide range of features that can help you with common conversion tasks:

Support for both OST and PST files comes as standard and the application can automatically search for Outlook files on your machine.
Calendar and contact information is also supported.
A sensible range of options for handling content in attachments is at your fingertips.
A range of filtering options lets you take control of your conversions and export only the fields you are interested in.

Whether you are looking to migrate your inboxes or export their contents to a particular format, you have two basic choices in terms of how you use Total Outlook Converter. Power users can bend the software to their will directly via the command line where a few keystrokes is all that is required. Those more comfortable with a screen-based approach will find Total Outlook Converter's intuitive GUI a breeze to use.

The software is also available in a version that can be integrated directly into your own application in the form of the ActiveX-enabled server license.

We have been developing our comprehensive range of conversion solutions for over a decade and you will struggle to find a more powerful solution than Total Outlook Converter at anything remotely resembling its affordable price.

Do not just take our word for it though. Download a 30-day free trial and discover the software's power for yourself before purchasing!

Total Outlook Converter Customer Reviews 2026

Rate ItRated 4.7/5 based on customer reviews

"A client wanted to leave Outlook behind entirely and move a large offline OST mailbox into Thunderbird. Total Outlook Converter exported thousands of messages in bulk to MBox files that Thunderbird opened without any import errors. Everything ran offline on the client's own PC, which mattered for their data-handling policy."

5 Star Peter Halvorsen IT Consultant, Halvorsen Systems

"We needed to migrate a donated researcher's OST archive into MBox format for long-term preservation in our SeaMonkey-compatible reading room setup. The batch conversion pulled out the full folder structure with the output fields we specified. It handled a mailbox far larger than the small test file I first tried it on."

5 Star Yolanda Ferreira Digital Archivist, university library system

"Moving OST mailboxes to MBox so Apple Mail users can inherit their old Windows-based Outlook history is now a routine part of my Mac switch projects. The one-click batch conversion handles most jobs without any hand-holding. Very large OST files occasionally need the attachment options double-checked before the final export."

4 Star Tobias Lindqvist Freelance Mac Migration Specialist

OST to MBox — FAQ ▼

How do I convert OST to MBox?

Install Total Outlook Converter, let it locate your OST file, select the folders and emails you want, click the MBox button, choose the output fields and attachment options, then click Start. The messages are exported to MBox files in bulk.

Can I convert OST to MBox in batch?

Yes. Migrating OST usually means thousands of files, and Total Outlook Converter is built for bulk processing that handles them in a single run.

Do I need Outlook installed to convert OST to MBox?

No. Support for both OST and PST files comes as standard, and the application can automatically search your machine for Outlook files and read them directly without Outlook open.

Which email clients open the resulting MBox files?

MBox is an open format read natively by Thunderbird, Apple Mail, SeaMonkey, Evolution, and most Unix-friendly clients. Import the MBox into the target client and the folder structure reappears.

Does OST to MBox conversion handle attachments and time zones?

Yes. You get a sensible range of options for handling attachment content, and you can synchronize emails that use different time formats so timestamps stay consistent.

Is converting OST to MBox free?

There is a fully functional 30-day free trial with no email or credit card required. A personal license costs $49.90 for unlimited use once the trial ends.

Can I convert OST to MBox from the command line?

Yes. Total Outlook Converter can be driven directly from the command line, and an ActiveX-enabled server version is available for integrating the conversion into your own applications.