West Fallowfield Township is a township in Chester County, Pennsylvania, United States. The population was 2,566 at the 2010 census.
According to the United States Census Bureau, the township has a total area of 18.1 square miles (47 km2), all of it land.
As of the census of 2000, there were 2,485 people, 829 households, and 674 families residing in the township. The population density was 137.5 people per square mile (53.1/km²). There were 858 housing units at an average density of 47.5/sq mi (18.3/km²). The racial makeup of the township was 96.54% White, 0.93% African American, 0.28% Native American, 0.24% Asian, 1.09% from other races, and 0.93% from two or more races. Hispanic or Latino of any race were 2.29% of the population.