Population of Counties in Colorado (2018)

Name 2018 Population Growth Since 2010
Denver County704,62116.81%
El Paso County699,23211.55%
Arapahoe County643,05211.90%
Jefferson County574,6137.26%
Adams County503,16713.41%
Larimer County343,97614.50%
Douglas County335,29916.85%
Boulder County322,5148.98%
Weld County304,63319.85%
Pueblo County166,4754.40%
Mesa County151,6163.55%
Broomfield County68,34121.57%
Garfield County59,1185.38%
La Plata County55,5898.28%
Eagle County54,7725.12%
Fremont County47,5591.56%
Montrose County41,7841.45%
Summit County30,5858.97%
Delta County30,568-0.94%
Morgan County28,192-0.15%
Montezuma County26,1402.21%
Elbert County25,64210.81%
Routt County25,2207.57%
Teller County24,6465.03%
Logan County21,896-1.10%
Chaffee County19,63810.29%
Otero County18,326-2.95%
Park County17,90510.01%
Pitkin County17,8904.28%
Gunnison County16,93910.32%
Alamosa County16,5513.85%
Grand County15,3213.56%
Las Animas County14,238-7.61%
Archuleta County13,31510.54%
Moffat County13,131-4.83%
Prowers County12,070-3.99%
Rio Grande County11,301-6.02%
Yuma County10,0750.23%
Clear Creek County9,5745.41%
Conejos County8,184-1.54%
San Miguel County7,9678.31%
Lake County7,7787.05%
Kit Carson County7,158-13.38%
Huerfano County6,662-0.25%
Saguache County6,6267.99%
Rio Blanco County6,420-3.72%
Gilpin County6,01310.09%
Bent County5,938-8.66%
Crowley County5,810-0.85%
Lincoln County5,5461.33%
Washington County4,9382.38%
Custer County4,87413.80%
Ouray County4,7947.80%
Phillips County4,292-4.03%
Costilla County3,7767.00%
Baca County3,562-6.46%
Sedgwick County2,344-1.01%
Dolores County2,067-0.10%
Cheyenne County1,8450.71%
Jackson County1,385-0.36%
Kiowa County1,376-1.99%
Hinsdale County794-5.92%
Mineral County7668.81%
San Juan County7150.99%