Carrigan Township is located in Marion County, Illinois. As of the 2010 census, its population was 380 and it contained 178 housing units.
Carrigan Township (T3N R1E) is centered at 38ð41'N 89ð5'W (89.689, -89.082). It is transversed northâÂÂsouth by U.S. Route 51 and eastâÂÂwest by the North Fork of the Kaskaskia River, on which the Carlyle Reservoir (El. 136 m) is located in the west part of the township. According to the 2010 census, the township has a total area of , all land.