County outline
Where Adams County is located
Area breakdown
Land accounts for 99.9% of Adams County’s measured area and water for 0.1%. Its combined area converts to 2,560.6 square kilometers or approximately 632,746 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 987.547 | 2,557.735 | 632,030.1 |
| Water | 1.118 | 2.896 | 715.5 |
| Total | 988.665 | 2,560.631 | 632,745.6 |
How Adams County compares
By original Census land area, Adams County ranks #40 of 53 in North Dakota and #698 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 0.85 times the North Dakota county-equivalent median of 1,161.8 square miles. It accounts for 1.4% of the combined county land area in the state.
See the complete North Dakota ranking · What counts as a county equivalent?
Population and density of Adams County
The Census Bureau estimates that 2,275 people lived in Adams County on July 1, 2025. That ranks #3,097 of 3,222 county equivalents nationally and #41 of 53 in North Dakota. Since the April 1, 2020 estimates base of 2,207, the population has grown by 68 (+3.1%), compared with +2.6% for North Dakota as a whole.
With 987.5 square miles of land, that is 2.3 people per square mile (0.89 per km²), placing Adams County #3,036 nationally for density and #40 in North Dakota. The median county equivalent has 47 people per square mile; the North Dakota median is 3.7. Put another way, there are about 278 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 2,194 | 2,169 | 2,121 | 2,188 | 2,220 | 2,275 |
| Change | — | −25 | −48 | +67 | +32 | +55 |
U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.
Cities and towns in Adams County
4 incorporated places lie at least partly in Adams County. Together they are home to 1,281 people (56.3%); the other 994 (43.7%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Hettinger city, with 1,119 residents in the county.
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Hettinger cityCounty seat | 1,119 | +2.4% | 0.829 |
| Reeder city | 130 | +4% | 0.687 |
| Haynes city | 17 | +6.3% | 0.135 |
| Bucyrus city | 15 | 0% | 0.35 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Adams County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Adams County is not part of any metropolitan or micropolitan statistical area in the Office of Management and Budget’s July 2023 delineation; 1,306 other county equivalents are also outside one. These areas are built around an urban core of at least 10,000 people plus the counties tied to it by commuting, so counties outside them are generally rural.
ZIP codes
6 ZIP Code Tabulation Areas have land in Adams County; 2 of them have most of their land inside the county, and the others mainly cover neighboring areas.
576385856258639586465864958650
ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.
Counties bordering Adams County
Adams County shares a land border with 7 county equivalents, including 2 in South Dakota. Each of them has more land than Adams County. The largest neighbor is Perkins County (2,870.5 mi²) and the smallest is Sioux County (1,094.1 mi²). Together with its neighbors, Adams County forms a block of 12,792.2 mi² of land, of which it holds 7.7%.
| Bordering county equivalent | Land mi² | Size vs. Adams | Compare |
|---|---|---|---|
| Perkins CountySouth Dakota | 2,870.5 | 2.9× larger | Compare |
| Harding CountySouth Dakota | 2,671.6 | 2.7× larger | Compare |
| Grant County | 1,659.2 | 1.7× larger | Compare |
| Slope County | 1,215.3 | 1.2× larger | Compare |
| Bowman County | 1,161.8 | 1.2× larger | Compare |
| Hettinger County | 1,132.2 | 1.1× larger | Compare |
| Sioux County | 1,094.1 | 1.1× larger | Compare |
How big is Adams County compared with U.S. states?
Adams County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1 times as much. North Dakota’s county land could hold about 70 areas the size of Adams County.
Another way to picture it: the same land area would fill a square about 31.4 miles (50.6 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.
State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.
What stands out about Adams County?
Adams County has more land than 2,524 of the other 3,221 county equivalents in the dataset.
A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.
Does including water change its rank?
Using land plus water places Adams County at #788 nationally by total area, 90 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.
Its water share is 0.1%, compared with a national county-equivalent median of 1.2% — 1.1 percentage points lower. This describes the statistical geography’s land/water mix, not flood exposure or developable land.
Closest positions in the national land ranking
These entries sit immediately beside Adams County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #697 | Jackson County, Wisconsin | 987.9 | Compare |
| #698 | Adams County, North Dakota | 987.5 | This county |
| #699 | Concho County, Texas | 983.8 | Compare |
Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.
Representative coordinates
The Census internal point is 46.096815, -102.533198. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.
Source and precision
U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 2,557,733,895 m²; AWATER: 2,894,336 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.
Common questions
How big is Adams County?
Adams County, North Dakota has 987.5 square miles (2,557.7 km²) of land and 1.118 square miles of water, for a total area of 988.7 square miles. It ranks #698 of 3,222 U.S. county equivalents by land area.
Is Adams County the largest county in North Dakota?
No. Adams County ranks #40 of 53 in North Dakota by land area. The largest is McKenzie County, with 2,760.1 square miles of land.
What counties border Adams County?
Adams County shares a land border with Hettinger County, Perkins County, South Dakota, Bowman County, Grant County, Sioux County, Slope County, and Harding County, South Dakota.
What is the population of Adams County?
The Census Bureau estimates Adams County had 2,275 residents on July 1, 2025, ranking #3,097 of 3,222 county equivalents. That is 2.3 people per square mile of land.
What is the county seat of Adams County?
The county seat of Adams County is Hettinger.
What cities and towns are in Adams County?
Adams County has 4 incorporated places. The most populous are Hettinger city, Reeder city, Haynes city, and Bucyrus city; 994 residents live outside any incorporated place.
Is Adams County part of a metropolitan area?
No. Adams County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Adams County?
6 ZIP Code Tabulation Areas have land in Adams County, and 2 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Adams County compare with U.S. states?
It has less land than every state. Rhode Island, the smallest, has 1 times as much land.
How many acres of land are in Adams County?
The land measurement converts to approximately 632,030 acres. Including water, total area is approximately 632,746 acres. One square mile equals 640 acres.
Why might another source show a different area?
Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.
Can this establish a property boundary?
No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.