Changanacherry is a municipal town in Kottayam district in the state of Kerala, India, located 18 km south of Kottayam and 8 km north of Thiruvalla on the Main Central road. With a population of about 50,000, it's population was already 36,000 as early as the 1951 census.

As of the 2001 India census, Changanassery had a population of 51,960. Males constituted 48% of the population and females 52%. Changanassery has an average literacy rate of 86%, higher than the national average of 59.5%; with male literacy of 86% and female literacy of 85%. 11% of the population is under 6 years of age. A large percentage of population from Changanassery resides abroad in the Gulf, Europe and America.

Perunna Subramanyaswami Temple, Thrikodithanam Temple, Vazhappally Mahadeven Temple, Metropolitan Church, Parel Church, Puthur Masjid (Puthurpally) and Pazhaya Masjid (Pazhayapally) are the important worship centres in Changanacherry. The notable worship centres near to Changanassery are Ettumanoor Temple, Manarkadu Church, Chakkulathukavu Temple, Neerettupuram, Chettikulangara Temple, Mavelikkara, Chengannur Mahadeva Temple and Anikkattilammakshethram Temple. The Archdiocese of Changanassery is the largest Catholic Diocese in India, established in 1887.