Postbox Express is a free version of the Postbox client without some tools. The application has typical functions related to the organization, creation, editing and receiving of mail. In addition to the usual functions, the program offers the possibility of creating libraries containing e-mail attachments.

The user can use the search engine to a limited extent - this applies e.g. to browsing history. There is a conversation view known from Gmail, a simplified view of folders and accounts, or integration with some applications.

Postbox Express supports POP, IMAP, RSS, mailing lists, as well as social services - Facebook and Twitter. In addition, the program has antiphishing protection. Allows you to import settings from mail clients such as Mozilla Thunderbird.