There are 53 counties in North Dakota. The most populous county in the state is Cass County, which is the only county to have over 100,000 people in North Dakota with 181,516. Fargo, the state’s most populous city, is in Cass County and accounts for 17% of the state’s population. Cass County comprises about 23.88% of North Dakota’s total population. The second-most populous county in North Dakota is Burleigh County, which has 95,273 residents, followed by Grand Forks County with 70,770 residents. Burleigh County is home to Bismarck, the state’s capital and second-most populous city.
Two North Dakota counties have populations under 1,000 residents. Slope County is the least populous county in North Dakota with 763 residents. Slope County’s population density is just 0.63 persons per square kilometer. Billings County is the second-least populous county in the state with 919 residents and a population density of 0.80 persons per square kilometer. Together, Slope County and Billings County make up only 0.22% of North Dakota’s total population.
The third-least populous state in North Dakota is Sheridan County, which has 1,349 residents.
Several counties in North Dakota have experienced double-digit growth, with one county seeing triple-digit growth since 2010. McKenzie County has seen a 112.63% growth since 2010. Despite this, McKenzie County has a population of just 13,632 residents.
Williams County has had the second-highest growth since 2010, growing by 56.50%. This is followed by Mountrail County (32.62%) and Stark County (27.25%). Other counties that have had double-digit growth include Dunn (22.51%), Cass (20.77%), Billings (17.37%), Burleigh (16.61%), and Morton (12.79%).