Although gross domestic product (GDP) per capita is a widely used and fundamental quantitative indicator for measuring individuals' living standards, the modern welfare literature emphasizes that policy design should not be limited solely to such economic indicators. The multidimensional and dynamic nature of social welfare makes it imperative and inevitable to go beyond GDP and similar macroeconomic variables and include qualitative measures such as happiness or subjective well-being. In this study, the determinants of happiness level are empirically examined by applying the Driscoll-Kraay (1998) Standard Error estimator technique on panel data of 27 European countries for the period 2010-2023. In addition to this technique, FGLS (Feasible Generalized Least Squares Method) and PCSE (Panel Corrected Standard Error Estimation) tests were also applied to ensure the reliability and consistency of the findings. The level of happiness is taken as the dependent variable while misery index, freedom index, trade openness rate and GDP per capita are taken as independent variables. According to the findings, poverty index and trade openness rate have negative and statistically significant effects on happiness, while freedom index and GDP per capita have positive and statistically significant effects. The results provide a multidimensional framework for the determinants of happiness and suggest that focusing only on economic variables is insufficient and that institutional structure and global integration should also be taken into account in policy design.