As of 2026, the age limit for London's iconic Black Cabs is strictly capped at 12 years. This is part of a phased environmental strategy by Transport for London (TfL) to reduce nitrogen oxide (NOx) emissions and improve the city's air quality. Previously, the limit was 15 years, but the regulations have been tightened to encourage the transition to "Zero Emission Capable" (ZEC) vehicles, such as the electric LEVC TX. Taxis that are older than 12 years are no longer eligible for a license to operate within the city. There is a small exception for "historically significant" vehicles or those that have been retrofitted with specific Euro 6-compliant engines, which may occasionally receive a short extension, but the vast majority of the fleet is now composed of much newer, cleaner models. This strict age limit ensures that the vehicles on the street are safe, modern, and environmentally responsible, though it has placed significant financial pressure on independent drivers who must now replace their vehicles more frequently than in decades past.