Gwinnett County area

Gwinnett County, Georgia covers 437.2 square miles: 431.2 square miles of land and 6.05 square miles of water. Its county seat is Lawrenceville. An estimated 1,018,099 people lived there in 2025.

Official Census measurements · GEOID 131352026 Gazetteer · retrieved September 27, 2026
Land area431.2 mi²
Water area6.05 mi²
Population (2025)1,018,099
People per mi²2,361

County outline

Generalized outline of Gwinnett 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 Gwinnett County is located

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

Area breakdown

Land accounts for 98.6% of Gwinnett County’s measured area and water for 1.4%. Its combined area converts to 1,132.3 square kilometers or approximately 279,809 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land431.1521,116.679275,937.3
Water6.0515.6693,872
Total437.2021,132.348279,809.3

How Gwinnett County compares

By original Census land area, Gwinnett County ranks #48 of 159 in Georgia and #2356 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 1.258 times the Georgia county-equivalent median of 342.7 square miles. It accounts for 0.7% of the combined county land area in the state.

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

Population and density of Gwinnett County

The Census Bureau estimates that 1,018,099 people lived in Gwinnett County on July 1, 2025. That ranks #49 of 3,222 county equivalents nationally and #2 of 159 in Georgia. Since the April 1, 2020 estimates base of 957,385, the population has grown by 60,714 (+6.3%), compared with +5.5% for Georgia as a whole.

With 431.2 square miles of land, that is 2,361 people per square mile (912 per km²), placing Gwinnett County #65 nationally for density and #2 in Georgia. The median county equivalent has 47 people per square mile; the Georgia median is 69. Put another way, there are about 0.271 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate958,317965,016979,814992,0581,009,8641,018,099
Change—+6,699+14,798+12,244+17,806+8,235

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 Gwinnett County

18 incorporated places lie at least partly in Gwinnett County. Together they are home to 303,180 people (29.8%); the other 714,919 (70.2%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Peachtree Corners city, with 42,519 residents in the county. The county seat, Lawrenceville city, has 32,822 residents. By land, Mulberry city is the largest at 25.7 mi². Among places with at least 1,000 residents in 2020, Braselton town grew fastest since then (+35.9%).

Incorporated placePopulation 2025Since 2020Land mi²
Peachtree Corners city42,519+0.6%16.3
Mulberry city41,445+5%25.7
Duluth city33,815+4.9%10.3
Lawrenceville cityCounty seat32,822+7.1%13.8
Sugar Hill city29,280+16.8%11.3
Suwanee city23,034+10.8%11.2
Snellville city22,478+9.3%10.5
Norcross city19,086+10.9%6.142
Lilburn city16,369+15.1%6.81
Buford cityAlso in 1 other county15,785+9.5%19.1
Dacula city9,373+35.8%5.401
Grayson city5,569+18.8%2.514
Braselton townAlso in 3 other counties5,461+35.9%13.2
Loganville cityAlso in 1 other county3,769+17.6%7.692
Berkeley Lake city2,034−0.4%1.74
Show the other 3 places
NamePopulation 2025Since 2020Land mi²
Auburn cityAlso in 1 other county281+33.2%7.335
Doraville cityAlso in 1 other county41+7.9%5.393
Rest Haven townAlso in 1 other county190%0.121

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

Metropolitan area

Gwinnett County is a central county of the Atlanta-Sandy Springs-Roswell, GA Metropolitan Statistical Area, in the Atlanta-Sandy Springs-Roswell, GA metropolitan division. Its 29 county equivalents have 6,482,182 residents on 8,784.1 square miles of land; Gwinnett County accounts for 4.9% of the land and 15.7% of the residents. By combined land it ranks #10 of 393 metropolitan areas, and #6 by population. It belongs to the Atlanta--Athens-Clarke County--Sandy Springs, GA-AL Combined Statistical Area.

County equivalentPopulation 2025Land mi²
Fulton County1,098,791526.9
Gwinnett County1,018,099431.2
Cobb County793,345339.7
DeKalb County774,394267.6
Cherokee County299,273421
Clayton County297,471141.7
Forsyth County282,805224.6
Henry County264,922318.7
Paulding County190,996312.4
Coweta County160,240441
Douglas County154,293200.1
Carroll County131,036499.1
Newton County125,583273.8
Fayette County125,156194.7
Bartow County120,800458.9
Walton County112,696326.8
Barrow County99,773161.1
Rockdale County98,416129.8
Spalding County70,775196
Pickens County37,167232.1
Lumpkin County36,178281.4
Dawson County35,365210.8
Haralson County33,066282.2
Butts County27,218183.7
Morgan County22,095347.4
Meriwether County21,516500.9
Pike County20,932216.1
Jasper County17,632368.4
Heard County12,149296

ZIP codes

26 ZIP Code Tabulation Areas have land in Gwinnett County; 16 of them have most of their land inside the county, and the others mainly cover neighboring areas.

3001130017300193002430039300433004430045300463004730052300713007830084300873009230093300963009730340303603051730518305193054830620

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 Gwinnett County

Gwinnett County shares a land border with 7 county equivalents. It has more land than 6 of them. The largest neighbor is Fulton County (526.9 mi²) and the smallest is Rockdale County (129.8 mi²). Together with its neighbors, Gwinnett County forms a block of 2,460.5 mi² of land, of which it holds 17.5%.

Map of Gwinnett County and the 7 county equivalents that border it DeKalb County, Georgia: 267.6 mi² landHall County, Georgia: 392.5 mi² landBarrow County, Georgia: 161.1 mi² landWalton County, Georgia: 326.8 mi² landFulton County, Georgia: 526.9 mi² landForsyth County, Georgia: 224.6 mi² landRockdale County, Georgia: 129.8 mi² land
Gwinnett 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. GwinnettCompare
Fulton County526.91.2× largerCompare
Hall County392.51.1× smallerCompare
Walton County326.81.3× smallerCompare
DeKalb County267.61.6× smallerCompare
Forsyth County224.61.9× smallerCompare
Barrow County161.12.7× smallerCompare
Rockdale County129.83.3× smallerCompare

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

Gwinnett County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 2.4 times as much. Georgia’s county land could hold about 134 areas the size of Gwinnett County.

Land area: Gwinnett County and the closest-sized states
Gwinnett County431.2 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 20.8 miles (33.4 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 Gwinnett County?

Gwinnett County has more land than 866 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Gwinnett County431.2 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 Gwinnett County at #2,399 nationally by total area, 43 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 1.4%, compared with a national county-equivalent median of 1.2% — 0.2 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 Gwinnett County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#2355Atchison County, Kansas431.2Compare
#2356Gwinnett County, Georgia431.2This county
#2357Clarke County, Iowa431.1Compare

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 33.958756, -84.025735. 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: 1,116,677,223 m²; AWATER: 15,668,815 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 Gwinnett County?

Gwinnett County, Georgia has 431.2 square miles (1,116.7 km²) of land and 6.05 square miles of water, for a total area of 437.2 square miles. It ranks #2356 of 3,222 U.S. county equivalents by land area.

Is Gwinnett County the largest county in Georgia?

No. Gwinnett County ranks #48 of 159 in Georgia by land area. The largest is Ware County, with 899.4 square miles of land.

What counties border Gwinnett County?

Gwinnett County shares a land border with DeKalb County, Hall County, Barrow County, Walton County, Fulton County, Forsyth County, and Rockdale County.

What is the population of Gwinnett County?

The Census Bureau estimates Gwinnett County had 1,018,099 residents on July 1, 2025, ranking #49 of 3,222 county equivalents. That is 2,361 people per square mile of land.

What is the county seat of Gwinnett County?

The county seat of Gwinnett County is Lawrenceville.

What cities and towns are in Gwinnett County?

Gwinnett County has 18 incorporated places. The most populous five are Peachtree Corners city, Mulberry city, Duluth city, Lawrenceville city, and Sugar Hill city; 714,919 residents live outside any incorporated place.

Is Gwinnett County part of a metropolitan area?

Yes. It is a central county of the Atlanta-Sandy Springs-Roswell, GA Metropolitan Statistical Area, which has 29 county equivalents and 6,482,182 residents.

How many ZIP codes are in Gwinnett County?

26 ZIP Code Tabulation Areas have land in Gwinnett County, and 16 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

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

It has less land than every state. Rhode Island, the smallest, has 2.4 times as much land.

How many acres of land are in Gwinnett County?

The land measurement converts to approximately 275,937 acres. Including water, total area is approximately 279,809 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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