Gunbarrel is a census-designated place (CDP) in Boulder County, Colorado, United States. The population was 9,263 at the 2010 census. Gunbarrel is a developed (built-up) area of Boulder County, but it is not an incorporated town or village. Gunbarrel locations may have postal addresses indicating Boulder, Niwot, or Longmont as the city.
The term Gunbarrel is also used colloquially to refer to a larger area, which includes parts of the city of Boulder and rural portions of Boulder County in addition to the CDP. However, this article is about the CDP specifically.