Importing MBOX files to Office 365 includes two major solutions: manual and professional. If we talk about the manual method, it is an indirect and techy process. Here's how to import MBOX to Office 365 manually:

1. Convert MBOX file into EML format.
2. Import EML file into Outlook.
3. Export file from Outlook to PST format.
4. Import PST file into Office 365

From the above discussion, we can conclude that importing a single MBOX file to Office 365 is a lengthy and tedious task. The file has to be converted four times to save in O365 which is enough complicated. To simplify the complete task, we recommend using the MBOX to Office 365 Migration Tool. It directly imports MBOX to Office 365 without any data loss. It supports bulk conversion of multiple MBOX files and provides 100% accuracy. Its interface is so simple that even a non-tech user can easily go through it. Download the free demo version of the tool to check out its features.