County outline
Where Cavalier County is located
Area breakdown
Land accounts for 98.6% of Cavalier County’s measured area and water for 1.4%. Its combined area converts to 3,910.5 square kilometers or approximately 966,294 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 1,489.125 | 3,856.816 | 953,040 |
| Water | 20.71 | 53.639 | 13,254.4 |
| Total | 1,509.835 | 3,910.455 | 966,294.4 |
How Cavalier County compares
By original Census land area, Cavalier County ranks #16 of 53 in North Dakota and #405 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.282 times the North Dakota county-equivalent median of 1,161.8 square miles. It accounts for 2.2% 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 Cavalier County
The Census Bureau estimates that 3,497 people lived in Cavalier County on July 1, 2025. That ranks #2,997 of 3,222 county equivalents nationally and #31 of 53 in North Dakota. Since the April 1, 2020 estimates base of 3,703, the population has declined by 206 (−5.6%), compared with +2.6% for North Dakota as a whole.
With 1,489.1 square miles of land, that is 2.3 people per square mile (0.91 per km²), placing Cavalier County #3,033 nationally for density and #39 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 273 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 3,697 | 3,678 | 3,615 | 3,589 | 3,546 | 3,497 |
| Change | — | −19 | −63 | −26 | −43 | −49 |
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 Cavalier County
12 incorporated places lie at least partly in Cavalier County. Together they are home to 2,243 people (64.1%); the other 1,254 (35.9%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Langdon city, with 1,809 residents in the county. By land, Alsen city is the largest at 29.4 mi².
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Langdon cityCounty seat | 1,809 | −5% | 1.547 |
| Munich city | 181 | −7.2% | 1.433 |
| Osnabrock city | 93 | −9.7% | 0.3 |
| Milton city | 39 | −7.1% | 0.471 |
| Alsen city | 29 | −6.5% | 29.4 |
| Nekoma city | 29 | −6.5% | 0.372 |
| Sarles cityAlso in 1 other county | 19 | −5% | 0.261 |
| Calvin city | 15 | −6.3% | 0.219 |
| Wales city | 8 | −11.1% | 0.242 |
| Calio city | 7 | 0% | 8.174 |
| Hannah city | 7 | −12.5% | 0.189 |
| Loma city | 7 | 0% | 26.5 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Cavalier County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Cavalier 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
18 ZIP Code Tabulation Areas have land in Cavalier County; 10 of them have most of their land inside the county, and the others mainly cover neighboring areas.
582205822758229582395824958255582605826958281582825831158323583305833858352583555837258377
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 Cavalier County
Cavalier County shares a land border with 4 county equivalents. It has more land than every one of them. The largest neighbor is Walsh County (1,281.6 mi²) and the smallest is Towner County (1,025.1 mi²). Together with its neighbors, Cavalier County forms a block of 6,099.8 mi² of land, of which it holds 24.4%.
| Bordering county equivalent | Land mi² | Size vs. Cavalier | Compare |
|---|---|---|---|
| Walsh County | 1,281.6 | 1.2× smaller | Compare |
| Ramsey County | 1,185.4 | 1.3× smaller | Compare |
| Pembina County | 1,118.5 | 1.3× smaller | Compare |
| Towner County | 1,025.1 | 1.5× smaller | Compare |
How big is Cavalier County compared with U.S. states?
Cavalier County has more land than 1 of the 50 states. It is about 1.4 times the land area of Rhode Island (1,033.9 mi²), while Delaware, the next larger state, has 1.3 times as much land (1,948.6 mi²). North Dakota’s county land could hold about 46 areas the size of Cavalier County.
Another way to picture it: the same land area would fill a square about 38.6 miles (62.1 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 Cavalier County?
Cavalier County has more land than 2,817 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 Cavalier County at #444 nationally by total area, 39 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 1.4%, compared with a national county-equivalent median of 1.2% — 0.2 percentage points higher. 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 Cavalier County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #404 | Lake County, Montana | 1,490.5 | Compare |
| #405 | Cavalier County, North Dakota | 1,489.1 | This county |
| #406 | La Salle County, Texas | 1,486.7 | 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 48.768439, -98.463790. 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: 3,856,816,540 m²; AWATER: 53,639,348 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 Cavalier County?
Cavalier County, North Dakota has 1,489.1 square miles (3,856.8 km²) of land and 20.7 square miles of water, for a total area of 1,509.8 square miles. It ranks #405 of 3,222 U.S. county equivalents by land area.
Is Cavalier County the largest county in North Dakota?
No. Cavalier County ranks #16 of 53 in North Dakota by land area. The largest is McKenzie County, with 2,760.1 square miles of land.
What counties border Cavalier County?
Cavalier County shares a land border with Pembina County, Towner County, Ramsey County, and Walsh County.
What is the population of Cavalier County?
The Census Bureau estimates Cavalier County had 3,497 residents on July 1, 2025, ranking #2,997 of 3,222 county equivalents. That is 2.3 people per square mile of land.
What is the county seat of Cavalier County?
The county seat of Cavalier County is Langdon.
What cities and towns are in Cavalier County?
Cavalier County has 12 incorporated places. The most populous five are Langdon city, Munich city, Osnabrock city, Milton city, and Alsen city; 1,254 residents live outside any incorporated place.
Is Cavalier County part of a metropolitan area?
No. Cavalier County is outside every metropolitan and micropolitan statistical area in the July 2023 OMB delineation.
How many ZIP codes are in Cavalier County?
18 ZIP Code Tabulation Areas have land in Cavalier County, and 10 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Cavalier County compare with U.S. states?
It has more land than 1 of the 50 states, including Rhode Island (1,033.9 square miles of land).
How many acres of land are in Cavalier County?
The land measurement converts to approximately 953,040 acres. Including water, total area is approximately 966,294 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.