Williams County, North Dakota
A county in North Dakota, ranked 5 of 53 by population.
CountyFIPS 38105
- Population
- 41,767
- +577 (+1.4%) since 2020
- Land area
- 2,078
- square miles. A further 3.3% of the total area is water
- Population density
- 20.1
- people per square mile, computed rather than published
- County seat
- Williston
- Seat of county government.
- Established
- 1891
- 134 years ago
- Largest city
- Williston city
- Population 29,522.
Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; Wikidata (CC0), Wikidata. Retrieved 30 August 2026.
Satellite view
Aerial imagery of Williams County with its boundary drawn on top. A map shows you the shape; this shows you what is inside it, and which side of the line a place falls on.
Where Williams County ranks
Position among the 53 counties of North Dakota, and among all 3,144 US counties and county-equivalents. Computed from the figures on this page.
| Measure | Value | In North Dakota | Nationally |
|---|---|---|---|
| Population | 41,767 | 5th of 53 | 1,162nd of 3,144 |
| Land area | 2,078 sq mi | 4th of 53 | 274th of 3,144 |
| Population density | 20.1 per sq mi | 6th of 53 | 2,244th of 3,144 |
| Median household income | $85,595 | 9th of 53 | 408th of 3,143 |
Full data for Williams County
| Measure | Value | Source and vintage |
|---|---|---|
| Population | 41,767 | Vintage 2025 Population Estimates |
| Population in 2020 | 41,190 | Vintage 2025 Population Estimates |
| 2020 estimates base? | 40,952 | Vintage 2025 Population Estimates |
| Land area | 2,078 sq mi | 2025 Gazetteer Files |
| Water area | 70.2 sq mi | 2025 Gazetteer Files |
| Total area | 2,148 sq mi | 2025 Gazetteer Files |
| Population density? | 20.1 per sq mi | Computed: Vintage 2025 estimates divided by 2025 Gazetteer land area |
| Median household income | $85,595 | American Community Survey 2020-2024 5-Year Estimates |
| Median home value | $284,800 | American Community Survey 2020-2024 5-Year Estimates |
| Median age | 31.8 | American Community Survey 2020-2024 5-Year Estimates |
| Households | 15,154 | American Community Survey 2020-2024 5-Year Estimates |
| Housing units | 20,376 | American Community Survey 2020-2024 5-Year Estimates |
Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026. Population density is computed here, not published: it divides the Vintage 2025 population estimate by the 2025 Gazetteer land area, which are two different Census products. Retrieved 30 August 2026.
How the population changed
The Census Bureau publishes the components behind an estimate, not just the total. For the year to July 2025:
- Births minus deaths
- +506
- 735 births, 229 deaths
- Net migration
- +506
- More people moved in than moved out.
Source: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026. Retrieved 30 August 2026.
The 7 areas bordering Williams County
Ordered by the length of the border actually shared, which the Census Bureau publishes in its county adjacency file and which no other county reference presents.
| Bordering area | State | Shared border | Population |
|---|---|---|---|
| McKenzie County | North Dakota | 97 mi | 15,192 |
| Divide County | North Dakota | 53 mi | 2,110 |
| Mountrail County | North Dakota | 32 mi | 9,395 |
| Roosevelt County | Montana | 27 mi | 10,242 |
| Sheridan County | Montana | 17 mi | 3,436 |
| Burke County | North Dakota | 6.0 mi | 2,132 |
| Richland County | Montana | a single point | 11,377 |
Source: US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. Retrieved 30 August 2026.
All 53 counties of North Dakota
Open the interactive North Dakota county map, or jump straight to any of them.
- Adams County
- Barnes County
- Benson County
- Billings County
- Bottineau County
- Bowman County
- Burke County
- Burleigh County
- Cass County
- Cavalier County
- Dickey County
- Divide County
- Dunn County
- Eddy County
- Emmons County
- Foster County
- Golden Valley County
- Grand Forks County
- Grant County
- Griggs County
- Hettinger County
- Kidder County
- LaMoure County
- Logan County
- McHenry County
- McIntosh County
- McKenzie County
- McLean County
- Mercer County
- Morton County
- Mountrail County
- Nelson County
- Oliver County
- Pembina County
- Pierce County
- Ramsey County
- Ransom County
- Renville County
- Richland County
- Rolette County
- Sargent County
- Sheridan County
- Sioux County
- Slope County
- Stark County
- Steele County
- Stutsman County
- Towner County
- Traill County
- Walsh County
- Ward County
- Wells County
- Williams County
Data on this page last rebuilt 30 August 2026. How these figures are produced.