Hays County area

Hays County, Texas covers 678.8 square miles: 676.9 square miles of land and 1.936 square miles of water. Its county seat is San Marcos. An estimated 304,390 people lived there in 2025.

Official Census measurements · GEOID 482092026 Gazetteer · retrieved September 27, 2026
Land area676.9 mi²
Water area1.936 mi²
Population (2025)304,390
People per mi²450

County outline

Generalized outline of Hays County, Texas
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 Hays County is located

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

Area breakdown

Land accounts for 99.7% of Hays County’s measured area and water for 0.3%. Its combined area converts to 1,758.1 square kilometers or approximately 434,431 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land676.8631,753.067433,192.3
Water1.9365.0141,239
Total678.7991,758.081434,431.4

How Hays County compares

By original Census land area, Hays County ranks #220 of 254 in Texas and #1386 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.745 times the Texas county-equivalent median of 908.7 square miles. It accounts for 0.3% of the combined county land area in the state.

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

Population and density of Hays County

The Census Bureau estimates that 304,390 people lived in Hays County on July 1, 2025. That ranks #243 of 3,222 county equivalents nationally and #19 of 254 in Texas. Since the April 1, 2020 estimates base of 241,064, the population has grown by 63,326 (+26.3%), compared with +8.8% for Texas as a whole.

With 676.9 square miles of land, that is 450 people per square mile (174 per km²), placing Hays County #377 nationally for density and #17 in Texas. The median county equivalent has 47 people per square mile; the Texas median is 22. Put another way, there are about 1.4 acres of land per resident.

Estimated population, 2020–2025 · line scaled to this county’s own range
July 1202020212022202320242025
Estimate243,984256,100269,554281,883294,339304,390
Change—+12,116+13,454+12,329+12,456+10,051

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 Hays County

13 incorporated places lie at least partly in Hays County. Together they are home to 184,380 people (60.6%); the other 120,010 (39.4%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is San Marcos city, with 77,830 residents in the county (the city extends into 2 other counties). By land, Austin city is the largest at 324.8 mi² across all its counties. Among places with at least 1,000 residents in 2020, Dripping Springs city grew fastest since then (+126.5%).

Incorporated placePopulation 2025Since 2020Land mi²
San Marcos cityCounty seat · Also in 2 other counties77,830+14.9%40.5
Kyle city69,917+53%32.6
Buda city16,166+6.8%9.913
Dripping Springs city11,167+126.5%8.815
Wimberley city2,909+1.9%8.903
Woodcreek city1,876+5%1.086
Uhland cityAlso in 1 other county1,273+24.2%4.055
Niederwald cityAlso in 1 other county912+73.4%3.667
Austin cityAlso in 3 other counties904+15.3%324.8
Mountain City city675+7.3%0.526
Bear Creek village476+19.9%1.141
Hays city271+18.9%0.223
Creedmoor cityAlso in 1 other county4+100%7.615

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

Metropolitan area

Hays County is a central county of the Austin-Round Rock-San Marcos, TX Metropolitan Statistical Area. Its 5 county equivalents have 2,620,945 residents on 4,219.9 square miles of land; Hays County accounts for 16% of the land and 11.6% of the residents. By combined land it ranks #67 of 393 metropolitan areas, and #25 by population.

County equivalentPopulation 2025Land mi²
Travis County1,389,670994.4
Williamson County752,8271,115.9
Hays County304,390676.9
Bastrop County118,908888.2
Caldwell County55,150544.5

ZIP codes

14 ZIP Code Tabulation Areas have land in Hays County; 7 of them have most of their land inside the county, and the others mainly cover neighboring areas.

7813078610786197862078623786407865278656786637866678676787367873778739

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 Hays County

Hays County shares a land border with 5 county equivalents. It has more land than 2 of them. The largest neighbor is Travis County (994.4 mi²) and the smallest is Caldwell County (544.5 mi²). Together with its neighbors, Hays County forms a block of 4,195.8 mi² of land, of which it holds 16.1%.

Map of Hays County and the 5 county equivalents that border it Travis County, Texas: 994.4 mi² landComal County, Texas: 559.5 mi² landBlanco County, Texas: 709.3 mi² landCaldwell County, Texas: 544.5 mi² landGuadalupe County, Texas: 711.2 mi² land
Hays 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. HaysCompare
Travis County994.41.5× largerCompare
Guadalupe County711.21.1× largerCompare
Blanco County709.3about the sameCompare
Comal County559.51.2× smallerCompare
Caldwell County544.51.2× smallerCompare

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

Hays County has less land than any of the 50 states. Rhode Island, the smallest state by land area, has 1,033.9 mi², about 1.5 times as much. Texas’s county land could hold about 386 areas the size of Hays County.

Land area: Hays County and the closest-sized states
Hays County676.9 mi²
Rhode Island1,033.9 mi²

Another way to picture it: the same land area would fill a square about 26 miles (41.9 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 Hays County?

Hays County has more land than 1,836 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Hays County676.9 mi²
Texas median908.7 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 Hays County at #1,498 nationally by total area, 112 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 0.3%, 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 Hays County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1385Garland County, Arkansas677.6Compare
#1386Hays County, Texas676.9This county
#1387Kankakee County, Illinois676.5Compare

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 30.061225, -98.029267. 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: 1,753,067,070 m²; AWATER: 5,015,352 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 Hays County?

Hays County, Texas has 676.9 square miles (1,753.1 km²) of land and 1.936 square miles of water, for a total area of 678.8 square miles. It ranks #1386 of 3,222 U.S. county equivalents by land area.

Is Hays County the largest county in Texas?

No. Hays County ranks #220 of 254 in Texas by land area. The largest is Brewster County, with 6,183.8 square miles of land.

What counties border Hays County?

Hays County shares a land border with Travis County, Comal County, Blanco County, Caldwell County, and Guadalupe County.

What is the population of Hays County?

The Census Bureau estimates Hays County had 304,390 residents on July 1, 2025, ranking #243 of 3,222 county equivalents. That is 450 people per square mile of land.

What is the county seat of Hays County?

The county seat of Hays County is San Marcos.

What cities and towns are in Hays County?

Hays County has 13 incorporated places. The most populous five are San Marcos city, Kyle city, Buda city, Dripping Springs city, and Wimberley city; 120,010 residents live outside any incorporated place.

Is Hays County part of a metropolitan area?

Yes. It is a central county of the Austin-Round Rock-San Marcos, TX Metropolitan Statistical Area, which has 5 county equivalents and 2,620,945 residents.

How many ZIP codes are in Hays County?

14 ZIP Code Tabulation Areas have land in Hays County, and 7 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.

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

It has less land than every state. Rhode Island, the smallest, has 1.5 times as much land.

How many acres of land are in Hays County?

The land measurement converts to approximately 433,192 acres. Including water, total area is approximately 434,431 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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