Permissibility of electoral systems and in particular the conversion of a plethora of voices in the electorate to the legislature is broadly considered to depend on the number of seats per district (district magnitude) in a country. Yet the most prevalent electoral system in the democratic world, proportional representation with districts, is often characterized by an almost entirely overlooked variation: within the same country districts vary in their magnitude, sometimes by a factor of twenty. How does such variation affect permissibility of electoral systems? Drawing on a broad cross-section of democracies, we demonstrate that contrary to what the literature implicitly assumes, other things equal, a combination of large and small districts results in greater permissibility than a set of districts of similar magnitude. We find that where districts are of similar (different) magnitude the degree of permissibility is lower (higher) than that found by current literature.