what county is sussex, wisconsin?
Sussex, Wisconsin. Sussex is a village in Waukesha County, Wisconsin, United States. It is approximately 19 miles (31 km) northwest of Milwaukee and 9 miles (14 km) north of Waukesha. The village is 7.24 square miles (19 km2) at an elevation of 930 feet. The population was 10,518 at the 2010 census.