How does regionalization affect national social policies? Although there is an extensive literature on the effects of globalization on social protection, the literature on the impact of regional integration is much less developed. I argue that the distinctive nature of regionalization processes calls for rigorous empirical testing of the domestic policy effects of regional integration. To this end, using an innovative dataset that measures the degree to which countries are integrated into regional economic and political organizations, this article uses statistical analysis to consider the influence of regional integration on government social spending. The results are surprising: regionalization has a significant and positive relationship with government social spending, controlling for other factors, even when the European Union countries are excluded from the analysis. In fact, in the EU countries increasing regionalization is associated with lower social spending levels. These results suggest that regional economic and political integration does not necessarily lead to a “race to the bottom” of social spending. Instead, regionalization appears to accommodate wide divergence in national social policy commitments.