Columbia is a town in Fluvanna County, Virginia, U.S., at the confluence of the James and Rivanna Rivers. The population was 49 at the 2000 census. It was the site of a minor battle during the Revolutionary War. According to the United States Census Bureau, the town has a total area of 0.5 km² (0.2 mi²). 0.5 km² (0.2 mi²) of it is land and 4.76% is water.

As of the census of 2000, there were 49 people, 18 households, and 12 families residing in the town. The population density was 94.6/km² (246.1/mi²). There were 22 housing units at an average density of 42.5/km² (110.5/mi²). The racial makeup of the town was 63.27% White, 28.57% African American, and 8.16% from two or more races. Hispanic or Latino of any race were 4.08% of the population. There were 18 households out of which 27.8% had children under the age of 18 living with them, 66.7% were married couples living together, 5.6% had a female householder with no husband present, and 27.8% were non-families. 16.7% of all households were made up of individuals and 11.1% had someone living alone who was 65 years of age or older. The average household size was 2.72 and the average family size was 3.23.