Introduction: The COVID-19 pandemic has caused a major crisis, affecting and straining the health care systems of even the most advanced countries. The diploma thesis initially studies the effects of the pandemic in Greece and other countries and the measures taken by the state to relieve the affected groups from the pandemic. Then the diploma thesis focuses on the primary care system which received the greatest pressure to deal with the unprecedented situation in which Greece found itself. They are analyzed the structure and mode of operation and the chronic problems faced by the health care system of Greece, due to the lack of strategy by the relevant agencies. Purpose: The purpose of the diploma thesis is to study the economic effects caused by the COVID-19 pandemic in the 7th Health Region of Crete, specifically in the Primary Health Care units particularly the Health Centers in the region. In particular, it is studying the costs for payroll, the costs for the additional materials required to deal with the pandemic and finally, expenses related to PCR tests for virus detection. Methodology: For the examination of the effects of the pandemic in the 7th Health Region of Crete, the costs and grants made in terms of payroll, supplies of health materials, and also they are presented other costs related to the operation of the7th Health Region of Crete. They are presented also, the rapid test, the cost of PCR tests for the Health Centers in the Heraklion Prefecture, as well as the vaccines carried out under the responsibility of the7th Health Region of Crete. Results: It appears that the average increase in the unit’s payroll is 8%. Finally, with regard to supplies of sanitary material, they increased by 981% in 2020, 2370% in 2021 and 240% in 2020.