Wealth Tax Mobility and Tax Coordination

Abstract

This paper studies the effects of decentralized wealth taxation on mobility and the effectiveness of tax coordination at mitigating potential inefficiencies and inequalities from wealth tax competition. Using linked administrative wealth and income tax records, we exploit the decentralization of the Spanish wealth tax, after which all regions except Madrid levied positive tax rates. We find that the mobility responses to wealth taxes are within the range of previous mobility estimates for income taxes. These mobility responses generate negative direct and cross-base fiscal externalities, with the losses to personal income tax revenues being six times larger than the direct losses to wealth tax revenues. Mobility also doubles the rate of growth of reported wealth among top wealth holders in the zero-tax jurisdiction. Finally, we show how the number of regions benefiting from tax harmonization depends critically on the cross-base effects of income taxes, but that a minimum tax rate is likely to receive the support of more regions than harmonization.

Keywords: Fiscal Decentralization, Fiscal Federalism, State and Local Taxation, Wealth Taxes, Mobility, Inequality, Tax Havens, Evasion

JEL Classification: E21, H24, H31, H73, J61, R23