The reintroduction and subsequent increases of the aviation tax in the Netherlands have raised questions regarding the leakage of Dutch passengers to nearby foreign airports. In 2027, the Netherlands is set to modify its existing aviation tax, creating a distance-based structure, while also heavily increasing the charged amounts. This study evaluates the expected impact of the tax increases on airport substitution, which exacerbates the leakage phenomenon. The calculation of the leakage for each postcode location in the Netherlands reveals an increase in foreign-airport departures among Dutch residents. The leakage is exacerbated, particularly among those living in the border regions and those embarking on medium and long-haul journeys, where the tax effects are the most prevalent. The findings highlight the increased probability of Dutch citizens selecting foreign departure airports in order to save additional funds. ... Read more