If your doctor is not yet participating in this new electronic transmission procedure or should this not work one time, you can upload the Arbeitsunfähigkeitsbescheinigung [statement of fitness for work] easily and securely via the TK-App or Meine TK (only available in German). Did your doctor transfer your statement of fitness for work electronically? In that case, you don't need to send us further proof.
More details
Alternatively, you can send the form to the following address (a street address is not required):
Techniker Krankenkasse
20908 Hamburg
Why not via e-mail?
Information about your health is subject to particularly stringent data protection requirements. An e-mail does not meet these requirements. It is like a postcard and can be read by anyone. Therefore, with the TK-App and "Meine TK" we offer you a secure means of transmission.