Yahoo Mail does not directly support MBOX file import; therefore, using a third-party tool is the easiest and fastest way to migrate emails from MBOX to Yahoo Mail. eSoftTools MBOX Converter software is a powerful tool that can upload your MBOX files directly to your Yahoo Mail account without any data loss and while preserving all email items (headers, attachments, and structure). Simply add the MBOX file to the software, preview your emails in preview mode, select the "Export to Yahoo/YMail" option, and then provide your Yahoo Mail login credentials to begin the import process. It seamlessly and securely uploads all emails and folder hierarchy from the MBOX file to your Yahoo Mail account, allowing you to access them instantly through the Yahoo web interface. This direct cloud migration method is far faster and more reliable than manual import.