Most of the people are Latin Catholics. The district includes Diocese of Cochin and Diocese of Alleppey. The local parishes in the Diocese of Cochin consist of St. Sebastian's Church in Chellanam, St. Antony's Church in Kannamaly, St. Joseph's Church in Cheriyakadavu and St. Francis of Assisi Church in Kattiparambu. Those in the Diocese of Alleppey are St. George's Church in Chellanam, Xavier Desh Church in South Chellanam, Littile Flower church Maruvakkadu and St. Francis Xavier's Church in Kandakkadavu.

Hindus belonging to communities such as Gowda Saraswatha Brahmins, Eazhava, Pulaya, Velan, Kudumbi, and Ulladan also live in Chellanam.