Pitkin County area

Population and density of Pitkin County

The Census Bureau estimates that 16,625 people lived in Pitkin County on July 1, 2025. That ranks #2,064 of 3,222 county equivalents nationally and #31 of 64 in Colorado. Since the April 1, 2020 estimates base of 17,362, the population has declined by 737 (−4.2%), compared with +4.1% for Colorado as a whole.

With 970.7 square miles of land, that is 17 people per square mile (6.6 per km²), placing Pitkin County #2,404 nationally for density and #27 in Colorado. The median county equivalent has 47 people per square mile; the Colorado median is 11. Put another way, there are about 37 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 Pitkin County

3 incorporated places lie at least partly in Pitkin County. Together they are home to 10,538 people (63.4%); the other 6,087 (36.6%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Aspen city, with 6,489 residents in the county. By land, Snowmass Village town is the largest at 27.8 mi². Among places with at least 1,000 residents in 2020, Basalt town grew fastest since then (+2.8%).

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

Metropolitan area

Pitkin County is an outlying county of the Rifle, CO Micropolitan Statistical Area. Its 2 county equivalents have 80,099 residents on 3,918.1 square miles of land; Pitkin County accounts for 24.8% of the land and 20.8% of the residents. By combined land it ranks #37 of 542 micropolitan areas, and #75 by population. It belongs to the Edwards-Rifle, CO Combined Statistical Area.

ZIP codes

8 ZIP Code Tabulation Areas have land in Pitkin County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.

8161181612816158162181623816428165481656

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 Pitkin County

Pitkin County shares a land border with 6 county equivalents. It has more land than 1 of them. The largest neighbor is Mesa County (3,328.7 mi²) and the smallest is Lake County (376.9 mi²). Together with its neighbors, Pitkin County forms a block of 13,560.8 mi² of land, of which it holds 7.2%.

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

Pitkin County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.1 times as much. Colorado’s county land could hold about 107 areas the size of Pitkin County.

Another way to picture it: the same land area would fill a square about 31.2 miles (50.1 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 Pitkin County?

Pitkin County has more land than 2,502 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 Pitkin County at #815 nationally by total area, 95 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 0.3%, compared with a national county-equivalent median of 1.2% — 0.9 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 Pitkin 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.