Simpson County area

Population and density of Simpson County

The Census Bureau estimates that 25,498 people lived in Simpson County on July 1, 2025. That ranks #1,652 of 3,222 county equivalents nationally and #35 of 82 in Mississippi. Since the April 1, 2020 estimates base of 25,941, the population has declined by 443 (−1.7%), compared with −0.2% for Mississippi as a whole.

With 589.2 square miles of land, that is 43 people per square mile (17 per km²), placing Simpson County #1,680 nationally for density and #40 in Mississippi. The median county equivalent has 47 people per square mile; the Mississippi median is 43. Put another way, there are about 15 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 Simpson County

4 incorporated places lie at least partly in Simpson County. Together they are home to 6,565 people (25.7%); the other 18,933 (74.3%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Magee city, with 3,904 residents in the county. The county seat, Mendenhall city, has 2,115 residents. By land, Mendenhall city is the largest at 5.348 mi².

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

Metropolitan area

Simpson County is an outlying county of the Jackson, MS Metropolitan Statistical Area. Its 8 county equivalents have 609,847 residents on 6,014.3 square miles of land; Simpson County accounts for 9.8% of the land and 4.2% of the residents. By combined land it ranks #36 of 393 metropolitan areas, and #97 by population. It belongs to the Jackson-Vicksburg-Brookhaven, MS Combined Statistical Area.

ZIP codes

10 ZIP Code Tabulation Areas have land in Simpson County; 6 of them have most of their land inside the county, and the others mainly cover neighboring areas.

39044390623907339078390823911139114391193914039149

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 Simpson County

Simpson County shares a land border with 6 county equivalents. It has more land than 3 of them. The largest neighbor is Copiah County (777.3 mi²) and the smallest is Jefferson Davis County (408.4 mi²). Together with its neighbors, Simpson County forms a block of 4,031.1 mi² of land, of which it holds 14.6%.

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

Simpson County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.8 times as much. Mississippi’s county land could hold about 80 areas the size of Simpson County.

Another way to picture it: the same land area would fill a square about 24.3 miles (39.1 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 Simpson County?

Simpson County has more land than 1,559 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 Simpson County at #1,779 nationally by total area, 116 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 0.2%, 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 Simpson 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.