To date, the empirical literature on spatial closures has focused on specific fleets and/or areas, and relatively less attention has been paid to the evaluation of responses to large-scale spatial restrictions on ocean fishing. Where such restrictions occur, a broad range of fleets may be affected, with diverse response mechanisms determining the redistribution of fishing effort and the associated welfare impacts. We propose a methodological approach to address such situations. Using hypothetical scenarios regarding the closure of the UK exclusive economic zone (EEZ) to a diverse subset of French vessels as an example, we develop a spatial discrete choice model that incorporates the possibility to adjust the resolution of choice sets at the fleet level to account for heterogeneous behavioral patterns across fleets. We show how neglecting fleet diversity in the choice of the spatial resolution of analysis may bias the results of an impact study on large spatial closures.