Ghaziabad in Uttar Pradesh was the most polluted Indian city in November 2025 with a monthly average PM2.5 concentration of 224 µg/m³, a report by the Centre for Research on Energy and Clean Air (CREA) stated. Ghaziabad was followed by Noida, Bahadurgarh, Delhi, Hapur, Greater Noida, Baghpat, Sonipat, Meerut and Rohtak. Delhi recorded nearly double the PM2.5 concentration of October.