Economic models assume that payroll tax burdens fall fully on workers, but where does tax incidence fall when taxes are firm-specific and time-varying? Unemployment insurance in the United States has the key feature of varying both across employers and over time, creating the potential for labor...

Equilibrium allocations in competitive labor market models are independent of whether labor taxes on firms are levied as employment taxes or payroll taxes, for given tax revenue. Turning to non-competitive labor market models, like wage bargaining of efficiency wage models, the two taxes cease...