Endogenizing take-up of social assistance in a microsimulation model: A case study for Germany

Microsimulation studies typically assume that all entitlements to means-tested benefits are actually claimed by eligible households, despite a large body of research that suggests that take-up rates are substantially below 100%. The assumption of full take-up tends to exaggerate the simulated increase in caseloads and fiscal costs of a social policy reform. This paper investigates the impact of non-take-up for two hypothetical scenarios, namely increasing and decreasing the base amount of social assistance in Germany by €100 per month. We find a substantial effect of considering non-take-up on the simulated change in fiscal costs and in particular on the change in caseloads, where the full take-up assumption exaggerates the latter change by a factor of about two.