The odd-even rule in Delhi is a traffic rationing measure that restricts access to public roads based on the last digit of a car's license plate. The rule allows vehicles with odd-numbered license plates to drive on odd dates, and vehicles with even-numbered plates to drive on even dates. For example, vehicles with license plates ending in 1, 3, 5, 7, or 9 are allowed to drive on odd dates, while vehicles with license plates ending in 0, 2, 4, 6, or 8 are allowed to drive on even dates.
The odd-even rule was implemented to reduce air pollution in New Delhi. During the first phase of the odd-even rule, there was a 15-20% reduction in traffic load and a 20% improvement in air quality levels. However, there was not a major impact on air quality during the second phase.
The odd-even rule was reintroduced in Delhi from November 13–20, 2023. During this time, only CNG, electric, and BS VI-compliant vehicles from other states were allowed to enter Delhi, with exemptions for essential services.
