Butte County area

Population and density of Butte County

The Census Bureau estimates that 2,783 people lived in Butte County on July 1, 2025. That ranks #3,049 of 3,222 county equivalents nationally and #42 of 44 in Idaho. Since the April 1, 2020 estimates base of 2,573, the population has grown by 210 (+8.2%), compared with +10.4% for Idaho as a whole.

With 2,236.5 square miles of land, that is 1.2 people per square mile (0.48 per km²), placing Butte County #3,126 nationally for density and #41 in Idaho. The median county equivalent has 47 people per square mile; the Idaho median is 10. Put another way, there are about 514 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 Butte County

3 incorporated places lie at least partly in Butte County. Together they are home to 1,181 people (42.4%); the other 1,602 (57.6%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Arco city, with 918 residents in the county.

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

Metropolitan area

Butte County is an outlying county of the Idaho Falls, ID Metropolitan Statistical Area. Its 3 county equivalents have 173,851 residents on 5,196.1 square miles of land; Butte County accounts for 43% of the land and 1.6% of the residents. By combined land it ranks #48 of 393 metropolitan areas, and #260 by population. It belongs to the Idaho Falls-Rexburg-Blackfoot, ID Combined Statistical Area.

ZIP codes

3 ZIP Code Tabulation Areas have land in Butte County, and each lies mostly inside the county.

832138324483255

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Butte County

Butte County shares a land border with 6 county equivalents. It has more land than 3 of them. The largest neighbor is Custer County (4,922.2 mi²) and the smallest is Jefferson County (1,093.7 mi²). Together with its neighbors, Butte County forms a block of 19,310.7 mi² of land, of which it holds 11.6%.

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

Butte 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 2.2 times as much land (4,842.5 mi²). Idaho’s county land could hold about 37 areas the size of Butte County.

Another way to picture it: the same land area would fill a square about 47.3 miles (76.1 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 Butte County?

Butte County has more land than 2,971 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 Butte County at #278 nationally by total area, 27 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 Butte 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.