As of the 2011 Census of India, the Erattupetta panchayat (now a municipality) had a population of approximately 29,675, though informal estimates suggest the broader urban agglomeration is significantly larger today.
The population is notable for its religious diversity and harmony, comprising a large Muslim majority alongside substantial Christian and Hindu communities. Like much of Kerala, Erattupetta boasts an exceptionally high literacy rate, typically exceeding 95%. The demographic profile includes a notable number of expatriates (NRIs) working in the Middle East, which profoundly influences local income levels, education standards, and consumption patterns.