Does the Composition of Wage and Payroll Taxes Matter Under Nash Bargaining?

Using the Nash bargaining approach to wage negotiations this paper shows that conventional wisdom, according to which the total tax wedge is the sum of wage and payroll taxes, is valid for equal tax bases, e.g., when the tax exemption takes the form of a tax credit. However, the equivalence result ceases to hold when the tax bases are unequal due to tax allowances. In this case a revenue-neutral restructuring of labour taxes toward a narrower tax base decreases the gross wage and is thus good for employment.