Using administrative linked employer-employee data for Norway we estimate the impact of changes in tax subsidies for union membership on individuals' membership probabilities. Increased subsidisation of the union good increases union take-up, while increased union fees reduce the demand for...

We exploit tax-induced exogenous variance in the price of union membership to identify the effects of changes in firm union density on firm productivity and wages in the population of Norwegian firms over the period 2001 to 2012. Increases in union density lead to substantial increases in firm...