ZIP Code 78656 — San Marcos city, TX Demographics & Data

ZIP code 78656 covers San Marcos, TX in Caldwell County with a population of about 2,953.

At a glance, the area shows median age of 32.6 versus a U.S. median of about 38.9.

It sits in telephone area codes 512, 737; U.S. House district TX-27; the AUSTIN media market.

Median household income in ZIP 78656 is about $78,058 — about 4% above the U.S. median ($75,149).

On socioeconomic markers, US5 shows a poverty rate of 7.3%; unemployment rate near 3.3%; 11.1% of adults with a bachelor’s degree or higher (about 22.6 points below the national share (33.7%)).

Labor and commute patterns include leading industry context around Construction, Retail trade, and Education; about 2.9% of workers reporting work-from-home (about 12.3 points below 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 $194,900 — about 44% below the U.S. median home value ($348,079).

Housing tenure and rents show median gross rent around $1,154 (about even with the U.S. median rent ($1,163)), and owner-occupancy near 63.5% (about 1.9 points below the national owner-occupancy rate (65.4%)).

To comfortably buy a median-priced home in ZIP 78656 in San Marcos, TX, a household would need roughly $54,000 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 $1,252. That sits below the local median household income ($78,058), suggesting the typical household income is closer to a workable buy-in level under these assumptions. 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 San Marcos city, TX as Relatively Low (composite score 79.8), which is elevated versus much of the country. The strongest component scores on US5 are flood (87.1) and wildfire (68.0). 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 San Marcos city, TX show little to no average snow and around 36.5 inches of annual precipitation.

IRS migration statistics show a net inflow of about 139 for ZIP 78656 (San Marcos 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.