In 2020, the municipality had a total population of 21,915,[1][2] up from 12,256 in 2005.[3]
In 2010, the town of Chalchihuitán had a population of 1,054.[2] Other than the town of Chalchihuitán, the municipality had 45 localities, the largest of which (with 2010 populations in parentheses) were: Chiquinshulum (1,612), classified as urban, and Joltealal (1,004), classified as rural.[2]