The terms of use of the ZRE (Federal Central Invoice Submission Portal) can be found at xrechnung.bund.de or down below. The terms of use of the OZG-RE (Online Access Act-compliant Invoice Submission Portal) can be found at xrechnung-bdr.de or down below. Compliance with the terms of use is a requirement for using the ZRE and OZG-RE invoice submission portals; the terms of use include all relevant information on the use of the portals.