The purpose of this paper is to investigate tax evasion through undeclared work incidents. It examines low taxation ethics observed from citizens and relates then to evasion levels connected to undeclared work. The research introduces a number of factors including different business sectors, a country's economic, sociological and political conditions. Furthermore, it investigates the phenomenon compared to inadequacies in state taxation and auditing mechanisms, as well as undeclared work's different types. The research was conducted in the second biggest industrial and economic centre of Greece in public administration organisations and accounting offices. The sample responded to closed questions questionnaire and the results showed that the low insurance and taxation ethics levels demonstrating by citizens are related most variables mentioned above. Overall, the study makes several