Bureau County area

Population and density of Bureau County

The Census Bureau estimates that 32,510 people lived in Bureau County on July 1, 2025. That ranks #1,422 of 3,222 county equivalents nationally and #46 of 102 in Illinois. Since the April 1, 2020 estimates base of 33,269, the population has declined by 759 (−2.3%), compared with −0.8% for Illinois as a whole.

With 869.1 square miles of land, that is 37 people per square mile (14 per km²), placing Bureau County #1,818 nationally for density and #64 in Illinois. The median county equivalent has 47 people per square mile; the Illinois median is 44. Put another way, there are about 17 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 Bureau County

25 incorporated places lie at least partly in Bureau County. Together they are home to 24,536 people (75.5%); the other 7,974 (24.5%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Princeton city, with 7,674 residents in the county. By land, Peru city is the largest at 10.4 mi² across all its counties. Among places with at least 1,000 residents in 2020, Ladd village grew fastest since then (+9.7%).

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

Metropolitan area

Bureau County is a central county of the Ottawa, IL Micropolitan Statistical Area. Its 3 county equivalents have 145,902 residents on 2,164.3 square miles of land; Bureau County accounts for 40.2% of the land and 22.3% of the residents. By combined land it ranks #73 of 542 micropolitan areas, and #9 by population. It belongs to the Chicago-Naperville, IL-IN-WI Combined Statistical Area.

ZIP codes

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

61283613126131461315613176132061322613236132861329613306133761338613426134461345613466134961354613566135961361613626136861374613766137961421614436153761560

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 Bureau County

Bureau County shares a land border with 7 county equivalents. It has more land than 6 of them. The largest neighbor is LaSalle County (1,135.1 mi²) and the smallest is Putnam County (160.1 mi²). Together with its neighbors, Bureau County forms a block of 5,071.3 mi² of land, of which it holds 17.1%.

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

Bureau County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.2 times as much. Illinois’s county land could hold about 64 areas the size of Bureau County.

Another way to picture it: the same land area would fill a square about 29.5 miles (47.4 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 Bureau County?

Bureau County has more land than 2,281 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 Bureau County at #1,039 nationally by total area, 98 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 0.5%, compared with a national county-equivalent median of 1.2% — 0.7 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 Bureau 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.