Cordon Tolls and Urban Traffic Volumes: Evidence from NYC's 2025 Congestion Relief Zone

On January 5, 2025, New York City became the first U.S. city to operate a permanent cordon-based congestion toll, charging vehicles entering Manhattan's Central Business District (the Congestion Relief Zone, or CRZ). This study estimates the short-run causal effect of the toll on hourly traffic volumes using a two-way fixed-effects difference in-differences (TWFE-DiD) strategy that compares treated CRZ street segments to untreated Manhattan segments north of 60th Street. The empirical analysis exploits hourly entry counts from the MTA's toll-meter system (4.86 million ten-minute-block records) as the primary descriptive panel and high-frequency NYC DOT Automated Traffic Recorder (ATR) data as the within-segment identification panel. The headline TWFE-DiD point estimate indicates a 40 to 45 percent reduction in log hourly volume at treated CRZ locations, with the effect direction consistent across nine pre-registered alternative specifications and concentrated in peak hours. East River bridges in the balanced panel exhibit a statistically significant 25 percent post-period increase in volume, consistent with route substitution.