TN · GEOID 47131

Obion County area

Obion County, Tennessee covers 555.4 square miles: 544.9 square miles of land and 10.6 square miles of water.

Official Census measurements2026 Gazetteer · retrieved September 27, 2026
Land area544.9 mi²
Water area10.6 mi²
Total area555.4 mi²
National land rank#1914

County outline

Generalized outline of Obion County, Tennessee
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Obion County is located

Obion County highlighted on a map of all U.S. county equivalents. About the maps

Area breakdown

Land accounts for 98.1% of Obion County’s measured area and water for 1.9%. Its combined area converts to 1,438.6 square kilometers or approximately 355,485 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land544.8511,411.158348,704.6
Water10.59527.4416,780.8
Total555.4461,438.599355,485.4

How Obion County compares

By original Census land area, Obion County ranks #26 of 95 in Tennessee and #1914 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.249 times the Tennessee county-equivalent median of 436.1 square miles. It accounts for 1.3% of the combined county land area in the state.

See the complete Tennessee ranking · What counts as a county equivalent?

What stands out about Obion County?

Obion County has more land than 1,308 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Obion County544.9 mi²
Tennessee median436.1 mi²
National median604.5 mi²

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.

Land rankCounty equivalentLand mi²Comparison
#1913Pike County, Pennsylvania544.9Compare
#1914Obion County, Tennessee544.9This county
#1915Thomas County, Georgia544.6Compare

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.

Representative coordinates

The Census internal point is 36.362912, -89.145776. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 1,411,156,596 m²; AWATER: 27,440,688 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How many acres of land are in Obion County?

The land measurement converts to approximately 348,705 acres. Including water, total area is approximately 355,485 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

Download the complete CSV or JSON dataset