Attributing PM2.5 and NO2 Changes One Year after New York City’s Congestion Pricing Policy

Abstract In January 2025, New York City implemented the Central Business District Tolling Program (CBDTP), a congestion pricing policy targeting lower Manhattan. We evaluate its first-year air quality effects using ground-based and satellite observations. Comparing New York City Community Air Survey (NYCCAS) real-time PM2.5 measurements from the first year of CBDTP with 2022–2024, we find statistically significant decreases within the congestion relief zone (CRZ). Difference-in-differences regression attributes a 1.44 μg/m3 PM2.5 reduction at CRZ sites to the CBDTP (p < 0.001). Accounting for spillovers, the CRZ decrease remained similar (1.33 μg/m3, p < 0.001), while nearby non-CRZ sites showed a nonsignificant 0.50 μg/m3 increase (p = 0.34). TROPOMI tropospheric NO2 columns declined over 20% across metropolitan NYC in 2025 relative to a 2018–2024 baseline. Decreases were larger in lower Manhattan than the outer boroughs, but not enough to be meaningfully attributed to the CBDTP, which was associated with a nonsignificant 1.23% decrease in tropospheric NO2 (p = 0.096). The program may nonetheless have contributed to the regional NO2 decline alongside other air quality policies. These findings offer critical early evidence that congestion pricing can deliver measurable air quality benefits, while contextualizing local improvements within the broader landscape.