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The introduction of Low Emission Zones (LEZs) is being considered as a policy measure to address the persistently high concentrations of local air pollutants observed across many urban areas of the United Kingdom and wider afield. These zones may substantially alter the operation of the transport system and could lead to adverse consequences for certain segments of the car-using population. Such consequences may include reductions in accessibility, whereby the ability of certain segments to travel to the zone is diminished. This paper considers this issue of accessibility by outlining a spatial vulnerability assessment for the city-region of Edinburgh, Scotland, which evaluates spatial units (in this case, DataZones) according to three criteria. First, a DataZone’s exposure to a LEZ is determined by using vehicle registration data to calculate the proportion of the privately owned car fleet that does not meet the compliance threshold and locally modelled origin-destination data to determine the degree of interaction by car between the DataZone and the LEZ. Second, a DataZone’s sensitivity to a LEZ is assessed by using the mean household income of the population. Third, the adaptive capacity of ‘potentially vulnerable’ (i.e. exposed and sensitive) DataZones to a LEZ is evaluated by measuring their proximity to direct public transport links to the LEZ, travel time from the LEZ, and level of physical disability. The paper concludes by demonstrating how the outputs of the assessment can inform LEZ policy development, mitigate adverse consequences on accessibility, and increase public acceptability.