Benton County area

Population and density of Benton County

The Census Bureau estimates that 26,004 people lived in Benton County on July 1, 2025. That ranks #1,630 of 3,222 county equivalents nationally and #24 of 99 in Iowa. Since the April 1, 2020 estimates base of 25,586, the population has grown by 418 (+1.6%), compared with +1.5% for Iowa as a whole.

With 716.1 square miles of land, that is 36 people per square mile (14 per km²), placing Benton County #1,842 nationally for density and #31 in Iowa. The median county equivalent has 47 people per square mile; the Iowa median is 26. Put another way, there are about 18 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 Benton County

14 incorporated places lie at least partly in Benton County. Together they are home to 17,280 people (66.5%); the other 8,724 (33.5%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Vinton city, with 5,004 residents in the county. Among places with at least 1,000 residents in 2020, Atkins city grew fastest since then (+7%).

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

Metropolitan area

Benton County is an outlying county of the Cedar Rapids, IA Metropolitan Statistical Area. Its 3 county equivalents have 279,285 residents on 2,008.7 square miles of land; Benton County accounts for 35.6% of the land and 9.3% of the residents. By combined land it ranks #157 of 393 metropolitan areas, and #184 by population. It belongs to the Cedar Rapids-Iowa City, IA Combined Statistical Area.

ZIP codes

24 ZIP Code Tabulation Areas have land in Benton County; 16 of them have most of their land inside the county, and the others mainly cover neighboring areas.

506515220652208522095221052213522245222552228522295224952257523015231352315523185232452332523455234652349523515235252354

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 Benton County

Benton County shares a land border with 5 county equivalents. It has more land than 3 of them. The largest neighbor is Tama County (721 mi²) and the smallest is Black Hawk County (565.8 mi²). Together with its neighbors, Benton County forms a block of 3,877.4 mi² of land, of which it holds 18.5%.

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

Benton County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.4 times as much. Iowa’s county land could hold about 78 areas the size of Benton County.

Another way to picture it: the same land area would fill a square about 26.8 miles (43.1 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 Benton County?

Benton County has more land than 1,957 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 Benton County at #1,379 nationally by total area, 114 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 Benton 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.