Cigati MBOX to Office 365 Migrator tool is a utility which can easily migrate or export the MBOX files into Office 365 and also Live Exchange Server. This software converts the MBOX files with all the attachments. It has an Intuitive Graphical User Interface which makes the work easy for the technical and non-technical users. It has the Mail Filter option where it performs selective migrations of emails.
Source: http://www.cigatisolutions.com/mbox-to-office365-migration/