In December 2022, the city of Sofia introduced one of the first low-emission zones (LEZ) for motorized vehicles in Central and Eastern Europe, following the example of 300 other cities across the continent. Despite its original intent as an effective measure to address the poor air quality, the current LEZ version lacks ambition in both design and execution, regardless of the published models, reports, and analyses, designed for the case of Sofia. Stakeholders were only partially engaged in the planning process and there was a lack of an public discussion.

The purpose of this analysis is to contribute to а well-designed and effective regulatory framework for Sofia’s LEZ and provide city-specific recommendations, based on European best practices, traffic models and implementation scenarios.