Hillsboro, WI has a population of 1,358 and is the 13,283rd largest city in the United States. The population density is 967 per sq mi which is 1006% higher than the Wisconsin average and 967% higher than the national average. The median age in Hillsboro is 40 which is approximately 3% higher than the Wisconsin average of 39. In Hillsboro, 58% of the population over 15 years of age are married, 98% speak English and 1% speak Spanish. 86% of Hillsboro residents were born in Wisconsin, 12% were born out of state, 1% were born outside of the United States and 1% were foreign born.