Use of Threema with external parties

The Federal Administration uses the Threema application for encrypted voice communication.

The IT directive "E027 – Application directive on encrypted voice communication" regulates how and when Threema is to be used for encrypted voice communication on smart devices that are integrated in the Federal Administration's Mobile Device Management (MDM) system. In particular, it contains provisions for handling sensitive information classified up to and including the CONFIDENTIAL level.

In order to communicate via Threema with individuals outside the Federal Administration and consequently with devices that are not integrated in the federal MDM (e.g. suppliers, members of the Armed Forces), it must be ensured that these individuals comply with the corresponding "User agreement" (appendix to "E027 – Application directive on encrypted voice communication) and confirm this.


In order to use Threema with external parties, the federal employee must send the link to the user agreement to the external party prior to the conversation. The external party must then

  • either confirm by email with an electronic signature that they have received, read and understood the user agreement (scan or photo of the handwritten signature),
  • or by message on Threema confirming that they have received, read and understood it.

It is important that this email or Threema message is saved and retained by the Federal Administration employee for reasons of evidence.

Last modification 25.03.2022

Top of page