Obion County area

Population and density of Obion County

The Census Bureau estimates that 30,067 people lived in Obion County on July 1, 2025. That ranks #1,482 of 3,222 county equivalents nationally and #50 of 95 in Tennessee. Since the April 1, 2020 estimates base of 30,795, the population has declined by 728 (−2.4%), compared with +5.8% for Tennessee as a whole.

With 544.9 square miles of land, that is 55 people per square mile (21 per km²), placing Obion County #1,456 nationally for density and #63 in Tennessee. The median county equivalent has 47 people per square mile; the Tennessee median is 76. Put another way, there are about 12 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 Obion County

10 incorporated places lie at least partly in Obion County. Together they are home to 17,132 people (57%); the other 12,935 (43%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Union City city, with 10,814 residents in the county.

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

Metropolitan area

Obion County is a central county of the Union City, TN Micropolitan Statistical Area. Obion County is the area’s only county equivalent, so the micro area has the same 544.9 square miles of land. By combined land it ranks #408 of 542 micropolitan areas, and #438 by population. It belongs to the Union City-Martin, TN Combined Statistical Area.

ZIP codes

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

380803823238233382373824038253382543825538257382593826038261

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 Obion County

Obion County shares a land border with 6 county equivalents, including 2 in Kentucky. It has more land than 4 of them. The largest neighbor is Gibson County (602.7 mi²) and the smallest is Lake County (165.8 mi²). Together with its neighbors, Obion County forms a block of 2,854.3 mi² of land, of which it holds 19.1%.

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

Obion County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.9 times as much. Tennessee’s county land could hold about 76 areas the size of Obion County.

Another way to picture it: the same land area would fill a square about 23.3 miles (37.6 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 Obion County?

Obion County has more land than 1,308 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 Obion County at #1,991 nationally by total area, 77 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 1.9%, compared with a national county-equivalent median of 1.2% — 0.7 percentage points higher. 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 Obion 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.