The article examines what causes budget deficits to fluctuate in European Union countries, focusing on both older and newer member states. By analyzing factors like government spending, economic growth, and unemployment, the study aims to understand how these variables affect budget stability. The goal is to find ways to reduce growing deficits and restore fiscal balance in line with new EU fiscal rules. The findings suggest that improving public sector efficiency and rethinking government intervention in the economy are crucial steps towards achieving fiscal stability.