Carbon County area

Population and density of Carbon County

The Census Bureau estimates that 11,466 people lived in Carbon County on July 1, 2025. That ranks #2,391 of 3,222 county equivalents nationally and #19 of 56 in Montana. Since the April 1, 2020 estimates base of 10,476, the population has grown by 990 (+9.5%), compared with +5.6% for Montana as a whole.

With 2,047.9 square miles of land, that is 5.6 people per square mile (2.2 per km²), placing Carbon County #2,819 nationally for density and #15 in Montana. The median county equivalent has 47 people per square mile; the Montana median is 2.8. Put another way, there are about 114 acres of land per resident.

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 Carbon County

5 incorporated places lie at least partly in Carbon County. Together they are home to 4,573 people (39.9%); the other 6,893 (60.1%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Red Lodge city, with 2,723 residents in the county.

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Carbon County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Carbon County is an outlying county of the Billings, MT Metropolitan Statistical Area. Its 3 county equivalents have 193,603 residents on 6,477.8 square miles of land; Carbon County accounts for 31.6% of the land and 5.9% of the residents. By combined land it ranks #29 of 393 metropolitan areas, and #242 by population.

ZIP codes

13 ZIP Code Tabulation Areas have land in Carbon County; 10 of them have most of their land inside the county, and the others mainly cover neighboring areas.

59001590075900859013590145901959026590295904159044590685907059071

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 Carbon County

Carbon County shares a land border with 6 county equivalents, including 2 in Wyoming. It has more land than 1 of them. The largest neighbor is Park County (6,939 mi²) and the smallest is Stillwater County (1,796.5 mi²). Together with its neighbors, Carbon County forms a block of 24,354.1 mi² of land, of which it holds 8.4%.

How big is Carbon County compared with U.S. states?

Carbon County has more land than 2 of the 50 states. It is about 1.1 times the land area of Delaware (1,948.6 mi²), while Connecticut, the next larger state, has 2.4 times as much land (4,842.5 mi²). Montana’s county land could hold about 71 areas the size of Carbon County.

Another way to picture it: the same land area would fill a square about 45.3 miles (72.8 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 Carbon County?

Carbon County has more land than 2,945 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 Carbon County at #308 nationally by total area, 31 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 0.7%, compared with a national county-equivalent median of 1.2% — 0.5 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 Carbon County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

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.