Allenspark is a census-designated place (CDP) in Boulder County, Colorado, United States. The population was 528 at the 2010 census. The Allenspark Post Office has the ZIP code 80510.
Allenspark is located in northwest Boulder County at 40°12′9″N 105°30′48″W / 40.20250°N 105.51333°W / 40.20250; -105.51333 (40.202416, -105.513341), within Roosevelt National Forest in the Front Range of the Colorado Rockies. The western edge of the community is the boundary of Rocky Mountain National Park. State Highway 7 passes through the community, leading north 15 miles (24 km) to Estes Park and east 19 miles (31 km) to Lyons. The center of Allenspark is at an elevation of 8,500 feet (2,600 m) above sea level.
According to the United States Census Bureau, the CDP has a total area of 11.8 square miles (30.5 km), of which 11.7 square miles (30.4 km) is land and 0.04 square miles (0.1 km), or 0.17%, is water.
As of the census of 2000, there were 496 people, 249 households, and 140 families residing in the CDP. The population density was 11.6 people per square mile (4.5/km²). There were 786 housing units at an average density of 18.4 per square mile (7.1/km²). The racial makeup of the CDP was 95.97% White, 0.20% African American, 0.60% Native American, 1.01% Asian, 0.60% from other races, and 1.61% from two or more races. Hispanic or Latino of any race were 1.61% of the population.
There were 249 households out of which 13.3% had children under the age of 18 living with them, 53.4% were married couples living together, 1.2% had a female householder with no husband present, and 43.4% were non-families. 35.3% of all households were made up of individuals and 8.8% had someone living alone who was 65 years of age or older. The average household size was 1.92 and the average family size was 2.45.
In the CDP, the population was spread out with 11.5% under the age of 18, 4.0% from 18 to 24, 27.4% from 25 to 44, 42.5% from 45 to 64, and 14.5% who were 65 years of age or older. The median age was 49 years. For every 100 females, there were 105.8 males. For every 100 females age 18 and over, there were 105.1 males.
The median income for a household in the CDP was $42,596, and the median income for a family was $65,536. Males had a median income of $27,857 versus $35,208 for females. The per capita income for the CDP was $28,333. None of the families and 10.0% of the population were living below the poverty line, including no under eighteens and 10.7% of those over 64.