Websites to PGP Encryption

OX Open-Xchange is a comprehensive web-based suite designed for communication, collaboration, and office productivity, offering features like email, calendaring, task management, and document sharing, seamlessly integrating across devices.

Posteo is a privacy-focused, secure email service based in Germany, offering paid accounts with strong encryption and transparency features. It emphasizes user data protection and operates on a green energy infrastructure.

Zimbra Collaboration Suite is a comprehensive open source email and collaboration platform designed for businesses. It provides a secure and feature-rich environment for email, calendaring, contacts, tasks, and file sharing, supporting on-premises and cloud deployments.

SOGo is a powerful open-source groupware server designed for scalability and simplicity. It provides a comprehensive suite of collaborative features including webmail, calendaring, contact management, and task management, with strong support for standard protocols like CalDAV and CardDAV.

Mailpile is a free and open-source webmail client designed with privacy and encryption as core principles. It offers a self-hostable solution for managing your email with built-in support for PGP encryption and other security features, providing an alternative to traditional webmail services.

ProtonMail is a leading secure email service utilizing end-to-end encryption and zero-access architecture to protect user privacy. Developed by scientists at CERN, it offers a robust and user-friendly platform for sending and receiving confidential communications.

Kolab Community is a comprehensive, free, and open-source groupware suite designed for collaborative work. It provides integrated email, calendar, contacts, and tasks functionalities, empowering individuals and teams to communicate and manage their data efficiently and with a strong focus on data privacy.

Lavabit was a highly secure, privacy-focused webmail service known for its strong encryption and commitment to user data protection, which ceased operations in 2013.