• county
  • FIPS 48491
  • Largest town: Round Rock

Williamson County, Texas

Williamson County had 727,480 residents in the Census Vintage 2024 estimate, on 1,115.9 square miles of land. It ranks 12th of 254 in Texas by population and 47th by land area.

Population
727,480
#12 of 254 in Texas · #96 in US
Area
1,115.9 sq mi
#47 of 254 in Texas · #565 in US
Density
652 / sq mi
#13 of 254 in Texas · #220 in US
Median household income
$111,183
#4 of 254 in Texas · #60 in US

Census Vintage 2024 estimates · SAIPE 2023 income · 2024 Gazetteer land area

Williamson County within Texas. Pin: Austin.

Measure from here

Tools and pages that start from Williamson County

Williamson County population, land area and income

Williamson County had 727,480 residents in the Census Vintage 2024 estimate, on 1,115.9 square miles of land. It ranks 12th of 254 in Texas by population and 47th by land area. That works out to 652.0 people per square mile, 6.8 times the US average of 96.3, and in the top tenth nationally.

The median county-equivalent in Texas has 19,267 residents, so Williamson County is 37.8 times that size.

Its SAIPE 2023 median household income of $111,183 is in the top tenth among 3,143 counties with an estimate.

National rank among 3,144

Population

727,480

3144th1st

96th of 3,144 (US)

Land area

1,116 sq mi

3144th1st

565th of 3,144 (US)

Density

652.0 / sq mi

3144th1st

220th of 3,144 (US)

Median household income

$111,183

3143rd1st

60th of 3,143 (US)

Rank within Texas (254)

Population

727,480

254th1st

12th of 254 (TX)

Land area

1,116 sq mi

254th1st

47th of 254 (TX)

Density

652.0 / sq mi

254th1st

13th of 254 (TX)

Median household income

$111,183

254th1st

4th of 254 (TX)

How Williamson County's population changed since 2020

Williamson County gained 111,849 residents between the July 2020 and July 2024 estimates, a rise of 18.2%. That ranks 11th of 254 in Texas for growth. The median Texas county changed by +2.1%, and the state as a whole by +7.0%.

Since the April 2020 estimates base, Williamson County recorded 33,004 births and 16,557 deaths, a natural change of +16,447. Net international migration added +16,547 and net domestic migration, people moving to or from other US counties, came to +85,666. The largest single component was domestic migration, which added 85,666 people.

615.6k2020644.7k2021674.0k2022701.6k2023727.5k2024
Census Vintage 2024 county estimates for July 1 of each year. The axis starts above zero so year-to-year changes are visible.

Components of change, April 2020 to July 2024

Births
33,004
Deaths
16,557
Net international migration
+16,547
Net domestic migration
+85,666
Change, July 2023 to July 2024
+25,840

Where Williamson County is

The Census internal point of Williamson County is at 30.649100, -97.605100. It sits in UTM zone 14N. The map shades Texas's 254 county-equivalents by population change from 2020 to 2024, darker for faster growth, with Williamson County outlined. Dots are towns of 1,000+ people with residents in it.

Cass County: +0.6%Jackson County: +1.9%Lipscomb County: -5.2%Hall County: +1.0%Hemphill County: -6.9%Kent County: -7.4%Dallam County: +5.4%Bandera County: +8.7%Culberson County: +3.1%Howard County: -11.4%Lavaca County: +1.2%Zavala County: -4.7%Taylor County: +3.7%Ellis County: +19.6%McLennan County: +3.5%Parker County: +20.2%Kinney County: +2.1%Uvalde County: +2.3%Haskell County: -0.0%Coke County: +2.3%Dickens County: -2.0%Colorado County: +4.0%Hansford County: -4.7%Collingsworth County: -1.2%Comanche County: +5.4%Crosby County: -1.3%Andrews County: +1.6%Atascosa County: +7.1%Brooks County: -5.0%Burnet County: +12.6%La Salle County: +0.4%Terry County: -1.6%Throckmorton County: +5.6%Yoakum County: -1.2%Hockley County: +0.0%Rockwall County: +25.5%Schleicher County: -5.8%Swisher County: -1.0%Motley County: -4.6%Hale County: -1.6%King County: -19.5%Hays County: +19.7%Irion County: +0.9%Bastrop County: +17.2%Blanco County: +16.6%Kimble County: +2.5%Dawson County: -5.7%Loving County: -28.4%Scurry County: -4.2%Sterling County: +0.2%Garza County: -20.1%Shackelford County: +1.9%Stonewall County: -0.8%Titus County: +0.8%Hopkins County: +5.3%Callahan County: +6.3%Childress County: +0.3%Lubbock County: +5.1%Dimmit County: -4.7%Donley County: -2.7%Baylor County: +2.1%Johnson County: +16.4%Glasscock County: +3.2%Sutton County: -2.6%Runnels County: -1.7%Ector County: +2.7%Kaufman County: +34.4%Jack County: +10.7%Mitchell County: -0.5%Falls County: +4.7%Castro County: +0.6%Palo Pinto County: +6.3%Limestone County: +1.9%Kerr County: +2.3%Franklin County: +5.2%Roberts County: +1.7%Young County: +2.2%Erath County: +4.2%Cochran County: +0.7%Hutchinson County: -4.2%Floyd County: -6.2%Mason County: +0.5%Parmer County: -1.9%Eastland County: +2.8%McMullen County: -5.4%Randall County: +6.5%Armstrong County: -2.3%Hamilton County: +4.8%Hartley County: -6.4%Nolan County: -3.7%Lynn County: +6.2%Menard County: -2.5%Karnes County: +2.2%Cottle County: -7.4%Winkler County: -4.8%Jeff Davis County: -10.4%Stephens County: +4.2%Bell County: +7.3%Borden County: -13.2%Madison County: +3.1%Fisher County: -0.3%Camp County: +5.9%Gillespie County: +5.2%Liberty County: +24.4%Upton County: -5.3%Waller County: +13.7%Fort Bend County: +15.6%Montgomery County: +19.9%Crockett County: -9.5%Sherman County: -0.7%Rusk County: +2.2%Wichita County: +0.3%Moore County: +2.8%Pecos County: -3.1%Webb County: +2.0%Kleberg County: -1.8%Fayette County: +4.0%Aransas County: +6.9%Presidio County: -6.9%Archer County: +7.0%Cherokee County: +5.2%Galveston County: +4.5%Comal County: +23.2%Concho County: +0.3%Jim Hogg County: -5.4%DeWitt County: +2.1%Brewster County: -0.6%Tarrant County: +5.4%Caldwell County: +14.1%Hardin County: +4.1%Fannin County: +7.4%Guadalupe County: +12.4%Clay County: +4.6%Coryell County: +3.9%Medina County: +8.9%Potter County: -3.1%Brown County: +1.5%Marion County: -1.7%Denton County: +14.3%Bee County: +0.6%Wise County: +17.9%Leon County: +5.8%Zapata County: -0.4%Coleman County: +4.0%Reagan County: -8.3%Mills County: +2.5%Reeves County: -19.0%Live Oak County: +5.5%Gaines County: +5.5%Oldham County: +3.4%Trinity County: +6.2%Williamson County: +18.2%San Saba County: -3.8%Wilson County: +10.7%Van Zandt County: +9.3%Lamar County: +2.2%Willacy County: -0.6%Brazos County: +6.4%Llano County: +8.7%Refugio County: -0.0%Martin County: -1.6%Midland County: +7.5%Wilbarger County: -3.0%Briscoe County: +5.1%Gonzales County: +1.8%Kenedy County: -5.7%Cameron County: +2.4%Gregg County: +1.9%Hidalgo County: +4.8%Hunt County: +18.4%Jefferson County: -0.9%Delta County: +8.1%Harris County: +5.8%Carson County: +0.5%Hill County: +7.8%Shelby County: +0.6%Hood County: +11.4%Grayson County: +10.6%Walker County: +9.4%McCulloch County: -1.8%Orange County: +1.6%Lee County: +5.4%Houston County: +0.6%San Jacinto County: +6.5%Robertson County: +5.3%Real County: +0.8%Red River County: +1.2%Sabine County: +1.7%Starr County: +1.1%Lamb County: -2.5%Goliad County: +2.8%El Paso County: +1.0%Wharton County: +1.1%Wheeler County: -3.1%Bexar County: +5.6%Lampasas County: +8.5%Calhoun County: -0.6%Maverick County: +1.7%Henderson County: +6.1%Freestone County: +6.2%Hardeman County: -4.0%Tom Green County: -0.1%Tyler County: +3.7%Chambers County: +19.5%Morris County: +1.8%Burleson County: +14.1%Newton County: -2.1%Upshur County: +7.3%Deaf Smith County: -0.2%Edwards County: -2.6%Bosque County: +4.2%Bowie County: -1.0%Matagorda County: +0.3%Terrell County: -4.3%Knox County: -2.9%Milam County: +5.6%Bailey County: +2.4%Nueces County: -0.1%Victoria County: +0.7%Dallas County: +1.7%Jones County: +5.9%Angelina County: +1.8%Washington County: +5.6%Gray County: -1.4%Grimes County: +13.6%Ochiltree County: -2.4%San Patricio County: +3.8%Val Verde County: +0.8%Foard County: -3.4%Frio County: +6.0%Kendall County: +16.3%Somervell County: +9.7%Panola County: +2.3%Nacogdoches County: +1.7%Ward County: -5.5%Wood County: +8.2%Montague County: +9.2%Duval County: -2.3%Navarro County: +6.9%Anderson County: +2.7%Jim Wells County: -0.0%Cooke County: +6.0%Rains County: +9.3%Austin County: +8.0%Brazoria County: +10.6%Polk County: +7.4%Travis County: +5.2%Collin County: +16.6%San Augustine County: -2.0%Harrison County: +3.7%Smith County: +6.4%Hudspeth County: +13.0%Crane County: -1.7%Jasper County: -0.0%
Change 2020 to 2024
  1. < -2.0%
  2. < +0.8%
  3. < +3.7%
  4. < +6.9%
  5. ≥ +6.9%
no data

Orange pin: Williamson County internal point. Dark pin: Austin.

Internal point

Decimal
30.649100, -97.605100
DMS
30°38'56.76"N 97°36'18.36"W
UTM
14N 633657.1E 3391544.0N
Geohash
9v6w6gqpu
Plus code
8624J9XV+JX

Towns in Williamson County

14 incorporated places of 1,000+ people have residents in Williamson County, 533,254 people together, or 73% of the county. Each figure counts only the part of the town inside Williamson County; towns marked "part" extend into another county. The largest is Round Rock with 133,441.

  1. 01Round Rock (part)133,441
  2. 02Georgetown101,344
  3. 03Leander (part)75,371
  4. 04Cedar Park (part)71,629
  5. 05Austin (part)70,212
  6. 06Hutto42,661
  7. 07Taylor17,872
  8. 08Liberty Hill11,984
  9. 09Jarrell5,151
  10. 10Florence1,211
  11. 11Granger1,209
  12. 12Bartlett (part)974
  13. 13Pflugerville (part)194
  14. 14Thorndale (part)1
Census Vintage 2024 subcounty estimates, county parts of incorporated places (SUMLEV 157).

Counties bordering Williamson County

The Census 2024 county adjacency file lists 6 neighbors for Williamson County. The most populous is Travis County, TX, with 1,363,767 residents. Distances run between Census internal points in a straight line.

Distance to Austin and the nearest big city

Austin is 27.1 miles SSW of Williamson County's internal point in a straight line. The nearest place of 100,000 or more is Georgetown, TX (population 101,344), 5.7 miles away.

Williamson County FIPS code

The FIPS code of Williamson County is 48491: state code 48 for Texas plus county code 491. Use it as text, with the leading zero, when joining Census, BLS, or CDC county tables. SAIPE lists its 2023 median household income as $111,183.

Questions people ask

What is the population of Williamson County, Texas?

The Census Vintage 2024 estimate for July 1, 2024 is 727,480. That is up 111,849 people (18.2%) from the July 2020 estimate of 615,631.

What is the FIPS code of Williamson County?

48491. The first two digits (48) are Texas; the last three (491) identify the county.

What is the largest town in Williamson County?

Round Rock, with 133,441 residents inside Williamson County in 2024 (135,359 across all 2 counties it spans).

Which counties border Williamson County?

6 county-equivalents border it in the Census 2024 adjacency file: Travis County, TX; Bell County, TX; Bastrop County, TX; Burnet County, TX; Milam County, TX; Lee County, TX.

Sources and data as of

Data as of: Census Vintage 2024 population estimates, 2024 Gazetteer land area and internal points, SAIPE 2023 median household income.

  1. 01Census Vintage 2024 county population estimates
  2. 02Census 2024 Gazetteer, counties
  3. 03Census SAIPE 2023 state and county estimates
  4. 04Census Vintage 2024 subcounty population estimates
  5. 05Census 2024 county adjacency file
  6. 06Census 2024 cartographic boundary file, counties (1:5,000,000)

How every number is computed: methodology. Spotted a wrong figure? Report an error.