This paper investigates differences in tax morale between the United States and Europe, using data from the World Values Survey (WVS). It finds that the United States has significantly higher tax morale than Spain and other European countries, with Austria and Switzerland following closely. The study also identifies a strong negative correlation between tax morale and the size of the shadow economy. Tax morale, defined as the intrinsic motivation to pay taxes, is influenced by cultural norms, trust in institutions, and religious beliefs. The research highlights the importance of social and institutional factors in shaping tax compliance behavior. The findings suggest that direct democratic traditions and strong institutional frameworks contribute to higher tax morale. The study also shows that tax morale varies across European countries, with Northern European countries having higher tax morale than Southern European countries. The results indicate that tax morale has real-world implications, influencing the size of the shadow economy. The paper emphasizes the need for further research into the determinants of tax morale and its effects on economic behavior.This paper investigates differences in tax morale between the United States and Europe, using data from the World Values Survey (WVS). It finds that the United States has significantly higher tax morale than Spain and other European countries, with Austria and Switzerland following closely. The study also identifies a strong negative correlation between tax morale and the size of the shadow economy. Tax morale, defined as the intrinsic motivation to pay taxes, is influenced by cultural norms, trust in institutions, and religious beliefs. The research highlights the importance of social and institutional factors in shaping tax compliance behavior. The findings suggest that direct democratic traditions and strong institutional frameworks contribute to higher tax morale. The study also shows that tax morale varies across European countries, with Northern European countries having higher tax morale than Southern European countries. The results indicate that tax morale has real-world implications, influencing the size of the shadow economy. The paper emphasizes the need for further research into the determinants of tax morale and its effects on economic behavior.