Deutsche Post’s E-Postbrief, sometimes shortened to E-Brief, is a hybrid postal service with an affiliated website for exchanging electronic messages over the internet. The goal of E-Postbrief is to offer greater authenticity, better data protection, and greater integrity than email, which is usually unencrypted and sometimes compared to a digital postcard.

E-Postbrief is designed to allow citizens, companies and public authorities to communicate electronically in a reliable, confidential fashion. The SSL-encrypted web portal makes it possible to send digital messages in the form of online letters between customers of the E Postbrief service. A digital E-Postbrief can only be used for communication between customers of the E Postbrief service. If an E-Postbrief recipient does not have an electronic mailbox provided by the service, the message will be printed, sealed and delivered by post as a hybrid E-Postbrief.

The service is advertised as making digital communication “just as binding, confidential and reliable” as mail. A verdict delivered by the Bonn District Court prohibited Deutsche Post from further promoting the product as such. As such, the service competes with the state-sponsored De-Mail service. A PostIdent verification – in which the applicant presents photo identification at a post office – is required for authentication during registration. As part of the application, the prospective user is sent a six-digit transaction number to their mobile phone by SMS.

Deutsche Post uses the HandyTAN process for this purpose. This process is also employed in order to use the E Postbrief portal. Later, the user is unambiguously identified by confirming their primary address. This is done by sending a new six-digit HandyTAN number and entering a one-time six-digit AddressTAN (sent by mail) into the E-Postbrief portal.