McDuffie County area

McDuffie County, Georgia covers 266.3 square miles: 257.4 square miles of land and 8.917 square miles of water. Its county seat is Thomson. An estimated 21,640 people lived there in 2025.

Official Census measurements · GEOID 131892026 Gazetteer · retrieved September 27, 2026
Land area257.4 mi²
Water area8.917 mi²
Population (2025)21,640
People per mi²84

County outline

Generalized outline of McDuffie County, Georgia
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 McDuffie County is located

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

Area breakdown

Land accounts for 96.7% of McDuffie County’s measured area and water for 3.3%. Its combined area converts to 689.7 square kilometers or approximately 170,429 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land257.379666.609164,722.6
Water8.91723.0955,706.9
Total266.296689.703170,429.4

How McDuffie County compares

By original Census land area, McDuffie County ranks #117 of 159 in Georgia and #2891 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.751 times the Georgia county-equivalent median of 342.7 square miles. It accounts for 0.4% of the combined county land area in the state.

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

Population and density of McDuffie County

The Census Bureau estimates that 21,640 people lived in McDuffie County on July 1, 2025. That ranks #1,795 of 3,222 county equivalents nationally and #84 of 159 in Georgia. Since the April 1, 2020 estimates base of 21,628, the population has grown by 12 (+0.1%), compared with +5.5% for Georgia as a whole.

With 257.4 square miles of land, that is 84 people per square mile (32 per km²), placing McDuffie County #1,116 nationally for density and #69 in Georgia. The median county equivalent has 47 people per square mile; the Georgia median is 69. Put another way, there are about 7.6 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate21,60921,63121,72621,85421,74321,640
Change—+22+95+128−111−103

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 McDuffie County

2 incorporated places lie at least partly in McDuffie County. Together they are home to 7,297 people (33.7%); the other 14,343 (66.3%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Thomson city, with 6,763 residents in the county.

Incorporated placePopulation 2025Since 2020Land mi²
Thomson cityCounty seat6,763−0.8%4.801
Dearing town534+0.4%0.815

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

Metropolitan area

McDuffie County is an outlying county of the Augusta-Richmond County, GA-SC Metropolitan Statistical Area. Its 7 county equivalents have 641,231 residents on 3,480.7 square miles of land; McDuffie County accounts for 7.4% of the land and 3.4% of the residents. By combined land it ranks #85 of 393 metropolitan areas, and #93 by population.

County equivalentPopulation 2025Land mi²
Richmond County206,559324.4
Aiken CountySouth Carolina181,5151,070.7
Columbia County169,189290.2
Edgefield CountySouth Carolina29,808500.7
Burke County24,408827
McDuffie County21,640257.4
Lincoln County8,112210.4

ZIP codes

4 ZIP Code Tabulation Areas have land in McDuffie County; 2 of them have most of their land inside the county, and the others mainly cover neighboring areas.

30802308083081430824

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 McDuffie County

McDuffie County shares a land border with 6 county equivalents. It has more land than 1 of them. The largest neighbor is Jefferson County (526.6 mi²) and the smallest is Lincoln County (210.4 mi²). Together with its neighbors, McDuffie County forms a block of 2,362.7 mi² of land, of which it holds 10.9%.

Map of McDuffie County and the 6 county equivalents that border it Warren County, Georgia: 284.4 mi² landColumbia County, Georgia: 290.2 mi² landWilkes County, Georgia: 469.5 mi² landRichmond County, Georgia: 324.4 mi² landLincoln County, Georgia: 210.4 mi² landJefferson County, Georgia: 526.6 mi² land
McDuffie County (dark) and its bordering county equivalents. Select a neighbor to open its profile. Drawn from the 2025 Census cartographic boundaries in an equal-area projection. How borders are determined.
Bordering county equivalentLand mi²Size vs. McDuffieCompare
Jefferson County526.62× largerCompare
Wilkes County469.51.8× largerCompare
Richmond County324.41.3× largerCompare
Columbia County290.21.1× largerCompare
Warren County284.41.1× largerCompare
Lincoln County210.41.2× smallerCompare

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

McDuffie County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 4 times as much. Georgia’s county land could hold about 224 areas the size of McDuffie County.

Land area: McDuffie County and the closest-sized states
McDuffie County257.4 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 16 miles (25.8 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 McDuffie County?

McDuffie County has more land than 331 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
McDuffie County257.4 mi²
Georgia median342.7 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 McDuffie County at #2,913 nationally by total area, 22 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 3.3%, compared with a national county-equivalent median of 1.2% — 2.2 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 McDuffie County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2890Grant County, Kentucky258Compare
#2891McDuffie County, Georgia257.4This county
#2892Essex County, Virginia257.4Compare

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 33.480610, -82.479572. 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: 666,608,430 m²; AWATER: 23,095,606 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 big is McDuffie County?

McDuffie County, Georgia has 257.4 square miles (666.6 km²) of land and 8.917 square miles of water, for a total area of 266.3 square miles. It ranks #2891 of 3,222 U.S. county equivalents by land area.

Is McDuffie County the largest county in Georgia?

No. McDuffie County ranks #117 of 159 in Georgia by land area. The largest is Ware County, with 899.4 square miles of land.

What counties border McDuffie County?

McDuffie County shares a land border with Warren County, Columbia County, Wilkes County, Richmond County, Lincoln County, and Jefferson County.

What is the population of McDuffie County?

The Census Bureau estimates McDuffie County had 21,640 residents on July 1, 2025, ranking #1,795 of 3,222 county equivalents. That is 84 people per square mile of land.

What is the county seat of McDuffie County?

The county seat of McDuffie County is Thomson.

What cities and towns are in McDuffie County?

McDuffie County has 2 incorporated places. The most populous are Thomson city and Dearing town; 14,343 residents live outside any incorporated place.

Is McDuffie County part of a metropolitan area?

Yes. It is an outlying county of the Augusta-Richmond County, GA-SC Metropolitan Statistical Area, which has 7 county equivalents and 641,231 residents.

How many ZIP codes are in McDuffie County?

4 ZIP Code Tabulation Areas have land in McDuffie County, and 2 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

How does McDuffie County compare with U.S. states?

It has less land than every state. Rhode Island, the smallest, has 4 times as much land.

How many acres of land are in McDuffie County?

The land measurement converts to approximately 164,723 acres. Including water, total area is approximately 170,429 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

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