ZIP code
20851
in Rockville, MarylandPopulation 14,946
64.32/ 100
Ranked #2,289 of 32,066 US ZIPs (top 7.2%)
Ranked #102 of 458 Maryland ZIPs (top 22%)
Ranked #133 of 308 Washington-Arlington-Alexandria, DC-VA-MD-WV ZIPs (top 43%)
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.
Lead in tap water
0 ppb
at the national minimum
Lower is healthier
US1stDefinition & source ›
The lead level at the 90th percentile of tap-water samples reported by the public water systems serving this ZIP, in parts per billion — the EPA requires action above 15 ppb.
Measured from EPA records for the public water systems that serve this ZIP. Households on private wells — roughly 30% of the US population — are not covered by this measure, and this figure says nothing about their water.
Full methodology ›Park land
23.4%
in the top 6.0% nationally
Higher is healthier
ST96thUS94thDefinition & source ›
The share of this ZIP’s land area that is public parkland.
Full methodology ›Hearing disability
4.8%
in the bottom 5.0% nationally
Lower is healthier
ST20thUS5thDefinition & source ›
The estimated share of adults who are deaf or have serious difficulty hearing.
Full methodology ›Obesity
26.9%
in the bottom 8.9% nationally
Lower is healthier
ST8thUS9thDefinition & source ›
The estimated share of adults with obesity, defined as a body-mass index of 30 or higher.
Full methodology ›Coronary heart disease
4.5%
in the bottom 5.7% nationally
Lower is healthier
ST11thUS6thDefinition & source ›
The estimated share of adults who have been told by a health professional that they have coronary heart disease or angina.
Full methodology ›Median household income
$126,411
in the top 7.8% nationally
Higher is healthier
ST67thUS92ndDefinition & source ›
The middle household income in this ZIP — half of households earn more, half earn less — in dollars per year.
Full methodology ›Mobility disability
9.2%
in the bottom 6.2% nationally
Lower is healthier
ST15thUS6thDefinition & source ›
The estimated share of adults with serious difficulty walking or climbing stairs.
Full methodology ›Air-toxics cancer risk
36.4 per million
in the top 8.6% nationally
Lower is healthier
ST86thUS91stDefinition & source ›
The EPA’s modeled estimate of added lifetime cancer risk from breathing outdoor air toxics, in cases per million people exposed over a lifetime.
Full methodology ›Walkability
110 intersections/sq mi
in the top 8.7% nationally
Higher is healthier
ST88thUS91stDefinition & source ›
The number of street intersections per square mile — a standard street-connectivity measure; denser networks correlate with more walkable neighborhoods.
Full methodology ›High blood pressure
28.5%
in the bottom 7.0% nationally
Lower is healthier
ST5thUS7thDefinition & source ›
The estimated share of adults who have been told by a health professional that they have high blood pressure.
Full methodology ›The read
ZIP 20851, one of several in Rockville, Maryland, by its overall standing, sits in the top 7.2% healthiest ZIPs nationally (2,289th) and the top 22% of Maryland (102nd).
Several good marks anchor the profile and deserve first mention: lead in tap water stands at the national minimum, park land lands in the top 6.0% nationally, and modeled hearing disability is in the bottom 5.0% nationally. Modeled obesity resides in the bottom 8.9% nationally, modeled coronary heart disease rests in the bottom 5.7% nationally, and household income lies in the top 7.8% nationally. Modeled mobility disability sits in the bottom 6.2% nationally, and walkability settles in the top 8.7% nationally. Modeled high blood pressure registers in the bottom 7.0% nationally. By contrast, modeled air-toxics cancer risk stands in the top 8.6% nationally.
Held up against its neighbors, park land runs far higher than the surrounding ZIPs on this measure. Defined in plain terms, lead in tap water is the EPA trigger, 15 parts per billion in tap samples, above which a water system must act on lead. Air-toxics cancer risk is a modeled EPA estimate of added lifetime cancer risk from breathing outdoor air, per million people. The nearest ZIP ranking healthier overall is ZIP 20850, just across the boundary.
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 Washington-Arlington-Alexandria, DC-VA-MD-WV 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 93%
21%
Social Need / SDOH
healthier than 77%
16%
Risk Behavior
healthier than 86%
11%
Mental Health
healthier than 92%
8%
Disability
healthier than 90%
7%
Healthcare Access
healthier than 76%
5%
About typical
Environmental Hazard
healthier than 59%
14%
Climate / Disaster Risk
healthier than 59%
5%
Holding it back
Preventive Care
healthier than 29%
13%
Lifting this score
Chronic Disease Burden
healthier than 94%
21%
Risk Behavior
healthier than 71%
11%
Mental Health
healthier than 82%
8%
Disability
healthier than 73%
7%
Climate / Disaster Risk
healthier than 60%
5%
Healthcare Access
healthier than 79%
5%
About typical
Social Need / SDOH
healthier than 53%
16%
Environmental Hazard
healthier than 45%
14%
Holding it back
Preventive Care
healthier than 8%
13%
Lifting this score
Chronic Disease Burden
healthier than 77%
21%
Mental Health
healthier than 70%
8%
Climate / Disaster Risk
healthier than 66%
5%
Healthcare Access
healthier than 66%
5%
About typical
Environmental Hazard
healthier than 54%
14%
Risk Behavior
healthier than 55%
11%
Disability
healthier than 57%
7%
Holding it back
Social Need / SDOH
healthier than 34%
16%
Preventive Care
healthier than 10%
13%
“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
20850
Marylandshares a border
Score 71.67
Closest healthier
20852
Marylandshares a border
Score 70.75
Similar health profile
94582
California99% similar profile
Score 75.45
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 | 18.0% | 16.5–19.5 |
| High blood pressure among adults | 28.5% | 26.4–30.6 |
| Cancer (non-skin) or melanoma among adults | 5.6% | 5.2–6.1 |
| Current asthma among adults | 9.1% | 8.1–10.0 |
| Coronary heart disease among adults | 4.5% | 4.1–5.0 |
| Chronic obstructive pulmonary disease among adults | 4.3% | 3.8–4.8 |
| Depression among adults | 18.2% | 16.2–20.1 |
| Diagnosed diabetes among adults | 9.9% | 8.9–11.0 |
| High cholesterol among adults who have ever been screened | 38.6% | 36.1–41.0 |
| Obesity among adults | 26.9% | 23.8–30.0 |
| Stroke among adults | 2.5% | 2.3–2.7 |
| All teeth lost among adults aged >=65 years | 10.9% | 9.1–12.8 |
PreventionCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Current lack of health insurance among adults aged 18-64 years | 12.5% | 10.7–14.5 |
| Taking medicine to control high blood pressure among adults with high blood pressure | 70.8% | 68.0–73.2 |
| Visits to doctor for routine checkup within the past year among adults | 73.4% | 70.7–75.9 |
| Cholesterol screening among adults | 88.1% | 86.7–89.5 |
| Colorectal cancer screening among adults aged 45–75 years | 63.9% | 60.8–67.0 |
| Visited dentist or dental clinic in the past year among adults | 62.3% | 59.9–64.6 |
| Mammography use among women aged 50-74 years | 77.8% | 73.2–81.9 |
Health Risk BehaviorsCDC PLACES 2022 / 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Binge drinking among adults | 14.8% | 13.0–16.7 |
| Current cigarette smoking among adults | 8.7% | 7.5–10.0 |
| No leisure-time physical activity among adults | 21.3% | 19.0–23.7 |
| Short sleep duration among adults | 35.6% | 32.7–38.6 |
Health StatusCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Fair or poor self-rated health status among adults | 17.1% | 15.4–19.0 |
| Frequent mental distress among adults | 13.7% | 12.3–15.0 |
| Frequent physical distress among adults | 11.0% | 9.9–12.2 |
DisabilityCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Cognitive disability among adults | 12.0% | 10.7–13.3 |
| Any disability among adults | 23.3% | 21.0–25.5 |
| Hearing disability among adults | 4.8% | 4.3–5.3 |
| Independent living disability among adults | 6.0% | 5.3–6.7 |
| Mobility disability among adults | 9.2% | 8.1–10.3 |
| Self-care disability among adults | 2.8% | 2.6–3.1 |
| Vision disability among adults | 4.4% | 4.0–4.8 |
Health-Related Social NeedsCDC PLACES 2023 · BRFSS
| Measure | Crude prevalence | 95% CI |
|---|---|---|
| Lack of social and emotional support among adults | 24.3% | 21.9–27.0 |
| Food insecurity in the past 12 months among adults | 15.6% | 13.7–17.9 |
| Received food stamps in the past 12 months among adults | 10.0% | 8.6–11.5 |
| Housing insecurity in the past 12 months among adults | 13.4% | 11.8–15.3 |
| Lack of reliable transportation in the past 12 months among adults | 7.5% | 6.6–8.4 |
| Loneliness among adults | 34.7% | 31.8–37.9 |
| Utility services shut-off threat in the past 12 months among adults | 7.1% | 6.2–8.1 |
Community & economyCensus ACS 5-Year · 2024 release · observed
| Measure | Value | US median (p10–p90) | MD median (p10–p90) |
|---|---|---|---|
| Poverty rate | 9.1% | 10.6% (3.1–25.8%) n=32,364 | 6.7% (1.1–19.3%) n=459 |
| Uninsured 18–64 | 13.6% | 9.0% (1.5–24.3%) n=32,286 | 4.8% (0.0–13.1%) n=459 |
| No HS diploma (25+) | 15.5% | 7.9% (1.8–20.7%) n=32,505 | 6.3% (0.5–16.6%) n=463 |
| Bachelor's or higher (25+) | 46.2% | 23.3% (9.2–53.6%) n=32,505 | 37.3% (15.0–64.4%) n=463 |
| Unemployment rate (16+) | 3.0% | 3.9% (0.0–9.8%) n=32,274 | 3.9% (0.0–8.6%) n=457 |
| Households without a vehicle | 7.4% | 3.9% (0.0–12.5%) n=32,322 | 3.2% (0.0–12.4%) n=457 |
| Broadband subscription | 92.8% | 89.3% (75.1–97.1%) n=32,322 | 93.3% (81.2–100.0%) n=457 |
| Housing cost burden (≥30% income) | 29.3% | 23.7% (10.6–40.0%) n=32,322 | 27.0% (12.0–41.8%) n=457 |
| Homeownership rate | 57.5% | 78.7% (51.7–94.0%) n=32,322 | 82.1% (49.9–98.5%) n=457 |
| Crowded housing (>1 per room) | 3.7% | 1.3% (0.0–6.3%) n=32,322 | 0.7% (0.0–4.0%) n=457 |
| Foreign-born population | 38.5% | 2.6% (0.0–18.6%) n=32,553 | 6.2% (0.0–26.4%) n=464 |
| Single-parent households | 43.0% | 53.6% (37.3–74.1%) n=32,087 | 50.9% (34.0–73.3%) n=450 |
| Population 65+ | 13.1% | 19.4% (10.8–33.6%) n=32,553 | 18.0% (10.9–33.1%) n=464 |
| Median age | 38.6 yr | 42.2 yr (33.0–56.3) n=32,292 | 41.8 yr (34.2–57.2) n=460 |
| Median household income | $126,411 | $72,070 ($46,039–$118,707) n=30,318 | $106,181 ($62,879–$172,423) n=419 |
| Median home value | $568,900 | $222,200 ($100,300–$579,820) n=30,049 | $423,400 ($215,180–$683,660) n=427 |
| Median gross rent | $2,043 | $1,021 ($677–$1,912) n=25,670 | $1,626 ($958–$2,415) n=339 |
Life expectancyNCHS / RWJF USALEEP · model-based
| Measure | Value | US median (p10–p90) | MD median (p10–p90) |
|---|---|---|---|
| Life expectancy at birth | 81.0 yr ± 0.90 | 78.9 yr (74.7–82.8) n=31,308 | 79.5 yr (75.7–82.7) n=451 |
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 0.90 years of 81.0, 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