ZIP code 78633

ZIP 78633 is a small city in Williamson County, Texas, with 28,877 residents counted in the Census American Community Survey 2019-2023 ACS 5-year estimates, which places it #399 of 1,989 ranked by population — larger than 79% of them. The median age here is 67.9 years against 39.1 nationally, a markedly older profile that usually tracks retirees staying put and younger households leaving for work. Places under 65,000 residents only appear in the five-year release, never the one-year file, so these values pool sixty months of responses and lag the current year by design.

Households in ZIP 78633 earn a median of $99,967 a year, 27.3% above the national figure of $78,538. This figure covers the household, not the worker: two people on ordinary wages at one address outrank a single professional in the same table. Poverty reaches 3.3% of residents here, less than half the 12.4% national rate.

The typical owner-occupied home in ZIP 78633 is valued at $443,500, 46.2% above the national figure, while median gross rent runs $1,836 a month, 30.6% above the national figure, or roughly $22,032 across a full year. A household on the local median income would put about 22% of gross pay toward that rent against the federal 30% cost-burden threshold, so renting here is within the standard affordability guideline. The home-price-to-income ratio works out to 4.4×, against roughly 3.9× nationally, so buying is harder here than in the average US market. 91.1% of occupied homes are owner-occupied versus 65% nationally, an owner-dominated market where rental listings are scarce and rent medians rest on a thin sample. Rent is reported gross — contract rent plus tenant-paid utilities — which is why it runs above the advertised price on a listing for the same unit.

A median age of 67.9 puts ZIP 78633 well into retirement-weighted territory, which pulls median household income down even where household wealth is high, because retirement draws are counted differently from wages.

All values below were released by the Census for this exact geography, with no gap-filling on our side. Small-area estimates still carry wider margins of error than state or national figures, so check the linked ACS tables before relying on them for lending, appraisal or legal work.

ZIP 78633 is tabulated inside Williamson County, Texas, one of 19 ZIP areas the Census publishes for that county and 1,989 across Texas. This is a mid-sized suburban ZIP inside a county that is split across many delivery areas. County assignment on this page follows the largest share of the ZIP's land area, which matters where a delivery route crosses a county line: mail addressed to 78633 can be handled by a post office in a neighbouring county even though the tabulation area is filed here.

Against its own county, 78633 reports a median household income of $99,967, close to the $101,250 county median, and 47% above the $68,103 typical TX ZIP. Owner-occupied homes are valued at a median of $443,500, 22% above the county figure and 128% above the statewide ZIP median. Rent is reported gross — the contract amount plus tenant-paid utilities — at $1,836 a month, which is why it reads higher than the advertised rent on a listing for the same unit.

Texas charges 6.25% statewide, and local governments overlapping 78633 may add county, city or special-district levies on top. We publish the state floor for this ZIP rather than guessing a combined figure, because ZIP boundaries and taxing-district boundaries were drawn for different purposes and do not line up.

Everything above comes from the Census Bureau American Community Survey 2019-2023 ACS 5-year estimates for this ZIP Code Tabulation Area, with sales tax rates traced to the state revenue agency. Five-year estimates pool sixty months of responses, so they are stable enough to compare 78633 with its neighbours but always trail the current year, and any value the Census suppressed for sample size is shown as unpublished rather than filled in with a model.