ZIP Code 78664 — Round Rock city, TX Demographics & Data

ZIP code 78664 covers Round Rock, TX in Williamson County with a population of about 62,272.

At a glance, the area shows median age of 34.8 versus a U.S. median of about 38.9.

It sits in telephone area codes 512, 737; U.S. House district TX-17; the AUSTIN media market.

Median household income in ZIP 78664 is about $85,919 — about 14% above the U.S. median ($75,149).

On socioeconomic markers, US5 shows a poverty rate of 10.5%; unemployment rate near 4.3%; 34.6% of adults with a bachelor’s degree or higher (roughly in line with the national share (33.7%)).

Labor and commute patterns include leading industry context around Retail trade, Professional services, and Healthcare; about 20.1% of workers reporting work-from-home (about 4.9 points above the U.S. share (15.2%)); a mean commute of about 180.0 minutes (U.S. average near 26.8).

Median home value is about $317,400 — about 9% below the U.S. median home value ($348,079).

Housing tenure and rents show median gross rent around $1,439 (about 24% above the U.S. median rent ($1,163)), and owner-occupancy near 54.1% (about 11.3 points below the national owner-occupancy rate (65.4%)).

To comfortably buy a median-priced home in ZIP 78664 in Round Rock, TX, a household would need roughly $87,000 in annual income under a 20% down, 30-year loan at 6.8% (illustrative), keeping housing costs near 28% of income. Estimated monthly PITI is about $2,039. That is roughly in line with the local median household income ($85,919). Rates, taxes, insurance, and HOA fees vary — treat this as a planning estimate, not a lender quote.

FEMA’s National Risk Index rates natural-hazard risk for Round Rock city, TX as Relatively Moderate (composite score 90.1), which is among the highest nationally. The strongest component scores on US5 are flood (91.3) and wildfire (87.8). These scores are county-linked NRI values published for planning context — all ZIP codes in the same county share the same composite score on US5. Useful when comparing insurance and disaster exposure across areas, not a substitute for a parcel-level flood or fire determination.

Climate normals for Round Rock city, TX show little to no average snow and around 37.1 inches of annual precipitation.

IRS migration statistics show a net inflow of about 2,937 for ZIP 78664 (Round Rock city, TX) on US5’s published series — a signal of people/tax filers moving in relative to those leaving. Inflows often track job growth, housing demand, or lifestyle migration; treat the figure as a directional indicator rather than a precise headcount.