London study reveals which airlines—led by Wizz Air, TAP Portugal, EasyJet and Lufthansa—offer the widest 18-inch economy seats for travelers craving elbow room.

LONDON — Fliers who dread brushing shoulders with neighbors have a new data point to consider before they click “book.” A consumer analysis out of London names the European carriers that give passengers the most—and least—elbow room in economy class, and in a world where every inch matters, the results could shape your next seat selection.