mailbox.org is a German email provider for private and business customers, with a strong emphasis on security, digital sovereignty, and data protection. In addition to core email functions, the platform offers calendar, address book, task management, office, drive, and video conferencing features. A basic mailbox is available from €1. Users include individuals, companies, schools, NGOs, and authorities such as the Thuringian Ministry of Education, Youth, and Sport. mailbox.org is a brand of Heinlein Support, specialists in email servers and Linux in data centres.