Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — STATE/TX/COUNTY/WILLIAMSON

Williamson County, TX ZIP codes

There are 26 ZIP codes in Williamson County, TX, in 16 towns, from 76527 to 78729. The largest are 78613 (Cedar Park), 78665 (Round Rock) and 78664 (Round Rock).

The county seat is Georgetown.

ZIP codes
26
Towns
16
County seat
Georgetown
County FIPS
48491
State
Texas
Population
672,688
Median household income
$111,340
Land area
1,116 sq mi
Area codes
512, 737

Williamson County ZIP codes by town

Georgetown (county seat)
78626, 78627, 78628, 78633

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

Map of Williamson County ZIP codes

7652776530765377657376574765787861378615786267862778628786307863378634786427864678664786657867378674786807868178682786837871778729

The ZIP codes of Williamson County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Williamson County in numbers

About 672,688 people live in Williamson County, in 252,323 households, the 12th most populous of Texas's 254 counties. The median household income is $111,340 a year, 42% above the Texas median of $78,476 (US: $80,734). The median owner-occupied home is valued at $447,000 (58% above the Texas median), and median gross rent is $1,796 a month. The median age is 37.3; 48.4% of adults 25 and over hold a bachelor's degree or higher (33.8% across Texas); the average commute takes 28 minutes.

Population672,688Williamson672,688
Households252,323Williamson252,323
Median age37.3Williamson37.3Texas35.6US 38.9
Median household income$111,340Williamson$111,340Texas$78,476US $80,734
Median home value$447,000Williamson$447,000Texas$283,800US $332,700
Median gross rent$1,796Williamson$1,796Texas$1,403US $1,413
Bachelor's degree or higher48.4%Williamson48.4%Texas33.8%US 35.7%
Mean commute27.9 minWilliamson27.9 minTexas26.7 minUS 26.4 min
Population density603 / sq miWilliamson603 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Williamson County

Largest towns in Williamson County
TownZIP codesPopulation
Austin 2 979,539
Round Rock 6 127,786
Georgetown 4 85,999
Cedar Park 2 78,301
Leander 1 74,067
Hutto 1 35,483
Taylor 1 17,136
Liberty Hill 1 8,371
Jarrell 1 3,295
Florence 1 1,061
Granger 1 1,046
Thrall 1 861
Coupland 1 491
Weir 1 434

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Williamson County.

Not sure you are in Williamson County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Williamson County, with figures

ZIP codes in Williamson County
ZIP City Type Population Median income Median home
76527 Florence , TX Standard 4,918 $81,574 $345,400
76530 Granger , TX Standard 2,598 $106,250 $288,300
76537 Jarrell , TX Standard 16,272 $98,199 $290,900
76573 Schwertner , TX Standard 0 — —
76574 Taylor , TX Standard 20,242 $78,568 $297,500
76578 Thrall , TX Standard 1,762 $105,063 $341,300
78613 Cedar Park , TX Standard 89,956 $125,487 $496,200
78615 Coupland , TX Standard 1,637 $80,938 $441,200
78626 Georgetown , TX Standard 48,072 $100,431 $387,700
78627 Georgetown , TX No street area — — —
78628 Georgetown , TX Standard 50,822 $125,635 $496,600
78630 Cedar Park , TX No street area — — —
78633 Georgetown , TX Standard 29,309 $100,936 $464,600
78634 Hutto , TX Standard 46,413 $114,426 $375,200
78642 Liberty Hill , TX Standard 26,434 $132,958 $506,600
78646 Leander , TX No street area — — —
78664 Round Rock , TX Standard 62,060 $87,417 $358,200
78665 Round Rock , TX Standard 66,171 $122,680 $474,100
78673 Walburg , TX No street area — — —
78674 Weir , TX Standard 108 — $47,500
78680 Round Rock , TX No street area — — —
78681 Round Rock , TX Standard 56,691 $137,819 $497,300
78682 Round Rock , TX No street area — — —
78683 Round Rock , TX No street area — — —
78717 Austin , TX Standard 37,262 $145,325 $652,200
78729 Austin , TX Standard 30,460 $86,438 $476,200

Cite this page

zipcodes.pro. “Williamson County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/tx/county/williamson

Underlying data is public domain or openly licensed — sources, vintages and licences.