Forest City is a village in Mason County, Illinois, United States. The population was 287 at the 2000 census.Forest City is located at 40°22′12″N 89°49′46″W / 40.37000°N 89.82944°W / 40.37000; -89.82944.According to the 2010 census, Forest City has a total area of 0.52 square miles, all land.As of the census of 2000, there were 287 people, 101 households, and 81 families residing in the village. The population density was 547.8 people per square mile. There were 105 housing units at an average density of 200.4 per square mile. The racial makeup of the village was 98.61% White, 1.05% Native American, and 0.35% from two or more races.There were 101 households out of which 32.7% had children under the age of 18 living with them, 73.3% were married couples living together, 5.0% had a female householder with no husband present, and 19.8% were non-families. 13.9% of all households were made up of individuals and 5.9% had someone living alone who was 65 years of age or older.