This study examines how political and fiscal decentralization are associated with subjective well-being across 140 European NUTS-2 regions using 2022 data. The results show that political decentralization is more strongly associated with life satisfaction in lower-governance regions in pooled models, suggesting a compensatory pattern. However, this relationship disappears once country fixed effects are introduced, indicating that the pooled association is driven primarily by cross-country institutional differences rather than robust within-country regional variation. Fiscal decentralization results are more mixed: broad expenditure, revenue, and transfer indicators are sensitive to specification, while regional discretion over personal income tax emerges as a more substantive form of fiscal autonomy within countries. Overall, the findings suggest that decentralization is not uniformly associated with higher well-being; its relationship with life satisfaction depends on the type of authority decentralized, governance quality, and broader national institutional context.