Abstract: We derive necessary and sufficient conditions on preferences for uniform taxation to be Pareto efficient in a many-consumer economy. We argue that uniformity is desirable only under conditions far more restrictive than suggested in previous literature, most of which is based on analysis of a single-consumer economy. When the only feasible direct tax is a poll tax, uniformity holds if and only if consumers have identical, linear Engel curves. When income can be redistributed optimally through direct taxes, uniformity also holds if wage elasticities of demand for all goods are constant and equal for all consumers.
JEL Classification: H21