ZIP code
78666
in San Marcos, TexasPopulation 88,583
48.70/ 100
Ranked #18,072 of 32,066 US ZIPs (bottom 44%)
Ranked #630 of 1,868 Texas ZIPs (top 34%)
Ranked #70 of 89 Austin-Round Rock-San Marcos, TX ZIPs (bottom 21%)
Ranks are modeled estimates — ZIPs a few hundred places apart are effectively tied.
What defines this ZIP
Metrics where this ZIP sits in the tails of the national distribution — the ones that most set it apart. Select any tile for its definition and methodology.
Subsidized affordable housing
2,436 units
in the top 0.2% nationally
Higher is healthier
ST99thUS99thDefinition & source ›
The number of affordable rental units in this ZIP supported by the federal Low-Income Housing Tax Credit program.
Full methodology ›Expected annual disaster loss
$1
in the top 1.4% nationally
Lower is healthier
ST98thUS99thDefinition & source ›
FEMA’s modeled estimate, in dollars per year, of the average harm to people expected from natural hazards — an annualized average, not a forecast for any single year.
Full methodology ›High cholesterol
28.3%
in the bottom 2.2% nationally
Lower is healthier
ST3rdUS2ndDefinition & source ›
The estimated share of adults with high cholesterol, among those who have ever been screened for it.
Full methodology ›Natural-disaster risk
in the top 2.0% nationally
Lower is healthier
ST96thUS98thDefinition & source ›
This area’s national rank on its single highest non-flood natural hazard — such as wildfire, tornado, or earthquake — in FEMA’s modeled National Risk Index; flooding is shown separately.
Full methodology ›Uninsured (under 65)
20.1%
in the top 4.5% nationally
Lower is healthier
ST67thUS96thDefinition & source ›
The estimated share of adults aged 18–64 with no current health-insurance coverage.
Full methodology ›Dry extreme heat
89.7 days/year
in the top 3.1% nationally
Lower is healthier
ST71stUS97thDefinition & source ›
The average number of days per year with a modeled daily high of at least 95 °F.
Full methodology ›High blood pressure
25.7%
in the bottom 3.4% nationally
Lower is healthier
ST4thUS3rdDefinition & source ›
The estimated share of adults who have been told by a health professional that they have high blood pressure.
Full methodology ›Humid extreme heat
150.5 days/year
in the top 4.6% nationally
Lower is healthier
ST72ndUS95thDefinition & source ›
The average number of days per year when modeled heat stress — temperature, humidity, sun, and wind combined — reaches levels hard on the body outdoors.
Full methodology ›Homeownership rate
38.1%
in the bottom 4.9% nationally
Higher is healthier
ST7thUS5thDefinition & source ›
The share of occupied homes that are owned, rather than rented, by the people living in them.
Full methodology ›Nitrate in drinking water
3.1%
in the top 5.0% nationally
Lower is healthier
ST88thUS95thDefinition & source ›
The modeled share of this area’s domestic-well groundwater at or above the federal nitrate limit of 10 milligrams per liter.
A modeled likelihood for untreated groundwater, the source drawn on by private wells, which are federally unregulated. It is not a measurement of treated water delivered by a public system, and it is not a test of any individual well.
Full methodology ›The read
Overall, San Marcos, Texas (ZIP 78666) lands in the bottom 44% nationally (18,072nd) and the top 34% of Texas (630th).
Several measures weigh most on this area's profile, and they come first: modeled expected annual loss resides in the top 1.4% nationally, and disaster risk registers in the top 2.0% nationally. Modeled uninsured rests in the top 4.5% nationally, and extreme heat stands in the top 3.1% nationally. Modeled humid heat lies in the top 4.6% nationally, homeownership lands in the bottom 4.9% nationally, and modeled nitrate sits in the top 5.0% nationally. On the better side, subsidized affordable housing is in the top 0.2% nationally, modeled high cholesterol settles in the bottom 2.2% nationally, and modeled high blood pressure resides in the bottom 3.4% nationally.
Set beside the nearby areas, subsidized affordable housing runs far higher than the surrounding ZIPs on this measure. A note on the terms: expected annual loss is FEMA's modeled estimate, in dollars, of average yearly harm to people from natural hazards. Disaster risk is the area's national rank on its highest non-flood peril in FEMA's modeled Risk Index, like wildfire or quake. Nitrate is a groundwater compound from fertilizer, manure, and sewage, here a modeled estimate of the chance private-well levels exceed a benchmark. For a healthier nearby comparison, ZIP 78130, just across the boundary, ranks better overall.
What’s driving this score
Nine domains make up the ZipVitals Score — here is how this ZIP does on each, and how much each one counts. Compare it against the US, this state and the Austin-Round Rock-San Marcos, TX metro area.
Compared with the ZIP codes measured across all nine scoring domains — not with all US ZIP codes.
Lifting this score
Chronic Disease Burden
healthier than 95%
21%
Social Need / SDOH
healthier than 68%
16%
Healthcare Access
in the top 0.00%
5%
About typical
Environmental Hazard
healthier than 46%
14%
Risk Behavior
healthier than 43%
11%
Disability
healthier than 49%
7%
Holding it back
Preventive Care
healthier than 3%
13%
Mental Health
healthier than 12%
8%
Climate / Disaster Risk
healthier than 7%
5%
Lifting this score
Chronic Disease Burden
healthier than 91%
21%
Social Need / SDOH
healthier than 68%
16%
Risk Behavior
healthier than 62%
11%
Healthcare Access
in the top 0.00%
5%
About typical
Disability
healthier than 59%
7%
Holding it back
Environmental Hazard
healthier than 29%
14%
Preventive Care
healthier than 10%
13%
Mental Health
healthier than 3%
8%
Climate / Disaster Risk
healthier than 32%
5%
Lifting this score
Healthcare Access
in the top 0.00%
5%
About typical
Chronic Disease Burden
healthier than 53%
21%
Holding it back
Social Need / SDOH
healthier than 27%
16%
Environmental Hazard
healthier than 1%
14%
Preventive Care
healthier than 10%
13%
Risk Behavior
healthier than 23%
11%
Mental Health
healthier than 1%
8%
Disability
healthier than 23%
7%
Climate / Disaster Risk
healthier than 30%
5%
“Share” is how much of this ZIP’s score the domain accounts for. Percentages are rounded; higher is healthier in every domain. How the score works, and who it compares you with ›
Nearby & similar ZIPs
Editorially selected — see how this ZIP compares to nearby and similar places.
Nearby
78130
Texasshares a border
Score 54.27
Closest healthier
78132
Texasshares a border
Score 61.88
Similar health profile
79410
Texas98% similar profile
Score 50.29
How these were chosen: only ZIPs with a published Score appear — a nearby ZIP with too little data to score won’t. Nearby means closest by distance between ZIP boundaries, which can cross state lines. A similar health profile is a close match across the nine Score domains, not similar demographics. Distances are measured between ZIP boundaries — ZIPs that touch share a border. How distance is measured
Evidence
Every measure this page draws on, by source. Collapsed by default — the full data stays in the page for search engines either way.
Health OutcomesCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Arthritis among adults | 16.3% | 14.5–18.2 |
| High blood pressure among adults | 25.7% | 22.9–28.7 |
| Cancer (non-skin) or melanoma among adults | 4.4% | 4.0–4.8 |
| Current asthma among adults | 10.3% | 9.2–11.6 |
| Coronary heart disease among adults | 4.3% | 3.9–4.7 |
| Chronic obstructive pulmonary disease among adults | 4.9% | 4.4–5.4 |
| Depression among adults | 24.8% | 21.5–28.4 |
| Diagnosed diabetes among adults | 9.3% | 8.2–10.4 |
| High cholesterol among adults who have ever been screened | 28.3% | 25.3–31.5 |
| Obesity among adults | 34.4% | 28.6–40.5 |
| Stroke among adults | 2.3% | 2.2–2.5 |
| All teeth lost among adults aged >=65 years | 13.5% | 11.3–16.1 |
PreventionCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Current lack of health insurance among adults aged 18-64 years | 20.1% | 18.0–22.2 |
| Taking medicine to control high blood pressure among adults with high blood pressure | 65.3% | 63.0–67.6 |
| Visits to doctor for routine checkup within the past year among adults | 69.0% | 64.8–73.0 |
| Cholesterol screening among adults | 76.3% | 73.7–78.7 |
| Colorectal cancer screening among adults aged 45–75 years | 60.2% | 55.9–64.7 |
| Visited dentist or dental clinic in the past year among adults | 51.1% | 47.9–54.7 |
| Mammography use among women aged 50-74 years | 70.3% | 63.2–77.1 |
Health Risk BehaviorsCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Binge drinking among adults | 19.1% | 16.0–22.4 |
| Current cigarette smoking among adults | 11.4% | 9.9–12.9 |
| No leisure-time physical activity among adults | 26.0% | 22.4–29.9 |
| Short sleep duration among adults | 36.5% | 31.6–42.1 |
Health StatusCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Fair or poor self-rated health status among adults | 21.6% | 19.3–24.1 |
| Frequent mental distress among adults | 21.2% | 19.0–23.5 |
| Frequent physical distress among adults | 12.5% | 11.1–14.0 |
DisabilityCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Cognitive disability among adults | 19.7% | 17.7–21.7 |
| Any disability among adults | 33.1% | 29.3–37.0 |
| Hearing disability among adults | 5.4% | 4.8–6.0 |
| Independent living disability among adults | 9.9% | 8.9–10.9 |
| Mobility disability among adults | 11.1% | 9.9–12.5 |
| Self-care disability among adults | 3.5% | 3.2–3.8 |
| Vision disability among adults | 6.4% | 5.9–6.9 |
Community & economyCensus ACS 5-Year · 2024 release · observed
| Measure | Value | US median (p10–p90) | TX median (p10–p90) |
|---|---|---|---|
| Poverty rate | 23.8% | 10.6% (3.1–25.8%) n=32,364 | 12.4% (3.5–26.4%) n=1,869 |
| Uninsured 18–64 | 20.9% | 9.0% (1.5–24.3%) n=32,286 | 22.3% (8.2–41.5%) n=1,862 |
| No HS diploma (25+) | 10.5% | 7.9% (1.8–20.7%) n=32,505 | 12.2% (2.5–30.0%) n=1,881 |
| Bachelor's or higher (25+) | 35.7% | 23.3% (9.2–53.6%) n=32,505 | 21.9% (9.0–51.4%) n=1,881 |
| Unemployment rate (16+) | 5.2% | 3.9% (0.0–9.8%) n=32,274 | 4.2% (0.0–9.4%) n=1,865 |
| Households without a vehicle | 7.5% | 3.9% (0.0–12.5%) n=32,322 | 3.7% (0.0–10.8%) n=1,868 |
| Broadband subscription | 86.4% | 89.3% (75.1–97.1%) n=32,322 | 89.2% (75.0–97.3%) n=1,868 |
| Housing cost burden (≥30% income) | 45.1% | 23.7% (10.6–40.0%) n=32,322 | 26.2% (8.8–40.3%) n=1,868 |
| Homeownership rate | 38.1% | 78.7% (51.7–94.0%) n=32,322 | 75.0% (46.4–92.3%) n=1,868 |
| Crowded housing (>1 per room) | 5.1% | 1.3% (0.0–6.3%) n=32,322 | 3.1% (0.0–9.0%) n=1,868 |
| Foreign-born population | 8.7% | 2.6% (0.0–18.6%) n=32,553 | 8.1% (0.1–26.4%) n=1,886 |
| Single-parent households | 50.7% | 53.6% (37.3–74.1%) n=32,087 | 48.5% (34.3–70.6%) n=1,861 |
| Population 65+ | 12.0% | 19.4% (10.8–33.6%) n=32,553 | 16.1% (8.6–30.1%) n=1,886 |
| Median age | 26.9 yr | 42.2 yr (33.0–56.3) n=32,292 | 38.3 yr (30.9–52.3) n=1,866 |
| Median household income | $54,737 | $72,070 ($46,039–$118,707) n=30,318 | $69,983 ($46,006–$112,413) n=1,737 |
| Median home value | $306,700 | $222,200 ($100,300–$579,820) n=30,049 | $210,500 ($97,060–$429,760) n=1,693 |
| Median gross rent | $1,319 | $1,021 ($677–$1,912) n=25,670 | $1,154 ($764–$1,815) n=1,508 |
Life expectancyNCHS / RWJF USALEEP · model-based
| Measure | Value | US median (p10–p90) | TX median (p10–p90) |
|---|---|---|---|
| Life expectancy at birth | 78.3 yr ± 0.48 | 78.9 yr (74.7–82.8) n=31,308 | 78.2 yr (75.1–81.7) n=1,772 |
About the ± — it’s this estimate’s give-or-take (statisticians call it the standard error). The true life expectancy for this ZIP most likely falls within 0.48 years of 78.3, and it’s very unlikely to be off by more than twice that.
More ZIPs to explore ▾More ZIPs to explore ▴
How these lists were built: they draw only from ZIPs that have a published Score, so ZIPs with too little data to score are not listed. Distance-based lists use distance between ZIP boundaries with no state filter, so an out-of-state ZIP can appear. Statistically similar means a close match across the nine Score domains, not a demographic match: the measure is the cosine similarity between two ZIPs’ domain scores, taken over the domains both ZIPs have data for and only where that overlap covers at least six of the nine — and where no ZIP clears that minimum-overlap floor, that list is left out rather than filled with a weak match. How distance is measured