Hallsville is a city in Boone County, Missouri, United States. It is part of the Columbia, Missouri Metropolitan Statistical Area. The population was 978 at the 2000 census.
Hallsville is located at 39°7′1″N 92°13′14″W / 39.11694°N 92.22056°W / 39.11694; -92.22056 (39.116956, -92.220571). According to the United States Census Bureau, the city has a total area of 0.7 square mile (1.9 km²), all land.
As of the census of 2000, there were 978 people, 404 households, and 275 families residing in the city. The population density was 1,334.2 people per square mile (517.3/km²). There were 439 housing units at an average density of 598.9 per square mile (232.2/km²). The racial makeup of the city was 96.42% White, 1.53% African American, 0.61% Native American, 0.31% from other races, and 1.12% from two or more races. Hispanic or Latino of any race were 0.72% of the population.