Youngest ZIP codes in Hays County, TX

These are the 8 ZIP codes in Hays County with the lowest median age, out of 8 with at least 1,000 residents. 78666 (San Marcos, 26.9), 78640 (Kyle, 33.4) and 78610 (Buda, 36.5) lead the list. There is no single "best" ZIP code in Hays County; the right one depends on who you want to reach, so the same ZIP codes are ranked several ways below.

Youngest ZIP codes in Hays County

RankZIPMailing cityMedian ageResidentsHouseholdsResidential mailboxes
178666San Marcos26.9 ±0.688,58333,94940,618
278640Kyle33.4 ±1.077,53127,37534,550
378610Buda36.5 ±1.248,31917,64023,159
478737Austin39.5 ±1.727,0239,1459,330
578652Manchaca41.8 ±3.85,2871,8693,196
678620Dripping Springs42.7 ±1.622,8608,27610,947
778619Driftwood44.8 ±8.56,6932,3932,500
878676Wimberley50.3 ±4.715,8227,0056,961

How we ranked them

Ranked by median age of all residents, lowest first (ACS 5-year estimates, 2020–2024). ZIP codes need at least 1,000 residents to be ranked; 8 of 8 qualify.

Which of these to mail, and why

Younger ZIP codes skew toward renters, students and young families: fitness, quick-service food, apartments, entertainment and first-time-buyer offers.

The top five ZIP codes on this list hold 89,978 households, on 119 carrier routes with 110,853 residential mailboxes. Open any of them on the route map to see each carrier route's own figures before you choose.

Open 78666 on the EDDM route map

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Frequently asked questions

Which ZIP code in Hays County has the lowest median age?
78666 (San Marcos), at 26.9 (±0.6), among 8 ZIP codes with at least 1,000 residents.
How is this ranking calculated?
Ranked by median age of all residents, lowest first (ACS 5-year estimates, 2020–2024).
Why are some ZIP codes missing?
ZIP codes with fewer than 1,000 residents are left out because their survey estimates swing too much to rank, and so are ZIP codes where the Census Bureau did not publish this figure.

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.