After receiving the Živnostenský list, you must register with the tax office (Finanční úřad) and the social insurance fund (ČSSZ) within 8 working days. It is also necessary to obtain health insurance. Czech citizens, holders of a residence permit or persons with an employment contract take out public health insurance, while students and entrepreneurs with only a residence permit take out commercial health insurance, as they are not always entitled to public insurance.
In some cases, registration with tax and insurance funds is automatic through Živnostenský úřad, but if this has not happened, you must perform these steps yourself. These are important steps to legally run your business and fulfill all mandatory state requirements.