The historic Town of Jamestown is a Statutory Town in Boulder County, Colorado, United States. The population was 274 at the 2010 United States Census. It was named for James Smith, an forward discoverer of gold. Jamestown was hit difficult by the September 2013 Colorado floods once the town was isolated due to road damage from the rains and the flooding of James Creek. Under a mandatory evacuation order, most residents were airlifted to safety under the handing out of the Colorado National Guard to within reach Boulder.

Jamestown is in central Boulder County at 40°6′56″N 105°23′15″W / 40.11556°N 105.38750°W / 40.11556; -105.38750 (40.115485, −105.387531). It lies along James Creek within the Front Range of the Colorado Rockies, with entry via James Canyon Drive, which leads east 8 miles (13 km) to U.S. Highway 36 in Altona and west 6.5 miles (10.5 km) to State Highway 72 (the Peak to Peak Highway) near Peaceful Valley. Jamestown’s height above sea level is 6,920 feet (2,110 m) above sea level.

According to the United States Census Bureau, the town has an Place of 0.62 square miles (1.6 km), all of it land.

As of the census of 2000, there were 205 people, 96 households, and 52 families residing in the town. The population density was 314.2 inhabitants per square mile (121.3/km²). There were 102 housing units at an average density of 156.3 per square mile (60.3/km). The racial makeup of the town was 97.56% White, 0.98% Asian, 0.49% Pacific Islander, and 0.98% from two or more races. Hispanic or Latino of any race were 0.49% of the population. There are now (2010) a couple of French people representing 0.98% of the people.