We study the welfare implications of two types of policies at the ZLB: (i) government spending; (ii) a tax cut financed with government debt. We show that, at the ZLB, government spending is always Pareto detrimental, irrespective of whether the economy features flexible or sticky prices, and of whether it features perfect or imperfect credit markets. A tax cut financed with government debt, by allowing an intertemporal redistribution between savers and constrained borrowers, is Pareto improving.