Who benefits from partial tax coordination?

In this paper, we investigate whether partial tax coordination is beneficial to countries within and outside a tax union, in which countries are supposed to compete in taxes and infrastructure. Our results demonstrate that, a subgroup of countries agreeing on a common tax rate, can harm both member and nonmember states. This is in contrast to the classical findings that partial tax harmonization is Pareto improving. When a minimum tax rate is imposed within a tax union, we demonstrate that it does not necessarily improve the welfare of the member countries. Moreover, both the high tax and low tax countries can be worse off. This is at odds with a classical result that a high tax country benefits from the imposition of a lower tax bound.