Rockville, MD · standard
ZIP Code 20851
Montgomery County, Maryland - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.
- 14,191
- 2,316/sq mi High-density area
- $126,411
- Median income Above-median income area
- $568,900
- Median home value Above-median home value
- 46.2%
- Bachelor's or higher Above-average bachelor's attainment
National ZIP placement
Rockville pairs a top-decile household income with top-decile home values, in a suburban-density, mixed-tenure area.
- Top 8%
- household income, US ZIPs
- Top 10%
- home value, US ZIPs
- 2,316
- people per sq mi
- 58%
- owner-occupied homes
Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 20851 against every reporting US ZIP.
FHFA HPI release change
What changed in the latest House Price Index year
- FHFA House Price Index values in ZIP 20851 (Rockville, MD) rose +5.1% from 2023 to 2024. The all-transactions index moved from 303.3 in 2023 to 318.6 in 2024 (2000 = 100).
ZIP code 20851 is a mid-sized community (a standard USPS delivery area) in Rockville, Montgomery County, Maryland, home to 14,191 residents across 6.1 square miles, a density of 2,316 people per square mile, in the New York time zone.
ZIP 20851 skews affluent, with a median household income of $126,411 (11% above the average Maryland ZIP), while per-capita income is $51,567. The poverty rate is 9.1%, with unemployment at 3.0%; those measures add context to the income figure. Median home value is $568,900 (27% above the average Maryland ZIP) and median rent is $2,043; 57.5% of occupied homes are owner-occupied.
A solid share of residents have a four-year degree: 46.2% of adults hold a bachelor's degree or higher, the median age is 38.6, and the average commute is 32 minutes. The page also surfaces 10 ZIP codes within roughly 10 miles and 6 more in Montgomery County, so 20851 can be compared with both its immediate and county-level context.
Every figure on this page is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates (including median rent) and the FHFA House Price Index, no estimates, no proprietary scoring. Verify with Census →
Top industries in ZIP 20851
Top 5 sectors by establishment count in Rockville, MD
Which industries have the most business establishments in ZIP 20851.
- Construction
Construction
32 establishments
- Other services (except public administration)
Other services (except public administration)
23 establishments
- Retail trade
Retail trade
22 establishments
- Professional, scientific, and technical services
Professional, scientific, and technical services
20 establishments
- Health care and social assistance
Health care and social assistance
18 establishments
What this shows Establishment counts come from the Census ZIP Code Business Patterns program, which counts physical business locations rather than employees or revenue.
Source: U.S. Census Bureau, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 20851, Rockville, MD · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; FHFA HPI updated quarterly/annually.
Quick Facts
14,191
Population
6.1
Area (sq mi)
2,316
People / sq mi
New York
Time Zone
standard
ZIP Type
Who lives in ZIP 20851?
38.6
Median Age
50.5%
Male
49.5%
Female
38.5%
Foreign-Born
Hispanic or Latino is an ethnicity category from the Census Bureau and may overlap with other categories above.
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How much do residents earn?
$126,411
Median Household Income
+11% vs state ZIP avg
$51,567
Per Capita Income
9.1%
Poverty Rate
3.0%
Unemployment Rate
31.8 min
Mean Commute Time
How ZIP 20851 ranks among Maryland ZIPs
Rockville, MD household income vs. every Maryland ZIP code
Median household income among 419 reporting Maryland ZIPs (this ZIP's population is too small for a reliable national-corpus placement)
$126,411 Top 33% higher than 67% of 419 Maryland ZIPs
Each bar is a $20K-wide band; taller bars hold more Maryland ZIPs. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source U.S. Census Bureau, ACS 5-Year Estimates · 2019–2023
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What is the education profile here?
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What does housing look like?
Housing stock: occupied vs vacant
5,338housing units
5,338
Total Housing Units
5,155
Occupied Units
183
Vacant Units
2.89
Avg Household Size
Occupancy Type
$568,900
Median Home Value
+27% vs state ZIP avg
$2,043
Median Rent
1959
Median Year Built
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How have home values changed over time?
FHFA House Price Index, annual appreciation data based on repeat sales and appraisals
+5.1%
YoY Change (2024)
319
HPI Index (2000 = 100)
+219%
Total Change Since 2000
Home values in ZIP 20851 have increased 5.1% over the past year (2024). Since 2000, this ZIP has seen +219% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2020 | +2.2% | 241 |
| 2021 | +10.6% | 266 |
| 2022 | +9.1% | 291 |
| 2023 | +4.4% | 303 |
| 2024 | +5.1% | 319 |
Source: Federal Housing Finance Agency (FHFA) House Price Index, All-Transactions, Five-Digit ZIP Codes (Developmental Index). Index base = 100 in year 2000. Data through 2024. ZIP codes with few transactions may show missing values.
What businesses operate in this ZIP?
Census Bureau data shows 168 business establishments in ZIP 20851, employing approximately 1,180 people with a combined annual payroll of $60,712,000.
168
Businesses
1,180
Employees
$60.7M
Annual Payroll
11
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Construction | 32 | 19.1% |
| Other services (except public administration) | 23 | 13.7% |
| Retail trade | 22 | 13.1% |
| Professional, scientific, and technical services | 20 | 11.9% |
| Health care and social assistance | 18 | 10.7% |
| Accommodation and food services | 16 | 9.5% |
| Administrative and support and waste management and remediation services | 11 | 6.5% |
| Real estate and rental and leasing | 6 | 3.6% |
| Manufacturing | 4 | 2.4% |
| Educational services | 4 | 2.4% |
| Arts, entertainment, and recreation | 3 | 1.8% |
Source: U.S. Census Bureau, ZIP Code Business Patterns (ZBP), 2023. Employment figures may include noise for disclosure avoidance.
Nearby ZIP Codes
Want a side-by-side? Compare 20851 vs 20852 →
ZIP 20851 vs its nearest neighbors, by population
Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 20906
Silver Spring (20906)
64,696 residents
- 20850
Rockville (20850)
46,340 residents
- 20852
Rockville (20852)
40,365 residents
- 20817
Bethesda (20817)
36,240 residents
- 20853
Rockville (20853)
29,673 residents
- 20814
Bethesda (20814)
27,642 residents
- 20895 19,054
Kensington (20895)
19,054 residents
- 20855 14,295
Derwood (20855)
14,295 residents
- 20851 14,191
Rockville (20851)
14,191 residents
What this shows Among its immediate neighbors, ZIP 20851 ranks #9 by population - useful context the national average alone can't give.
ZIP 20851 vs its nearest neighbors, by median income
Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 20896
Garrett Park (20896)
$250,000 median income
- 20817
Bethesda (20817)
$249,332 median income
- 20895
Kensington (20895)
$173,625 median income
- 20853
Rockville (20853)
$159,080 median income
- 20814
Bethesda (20814)
$150,996 median income
- 20855
Derwood (20855)
$149,110 median income
- 20880
Washington Grove (20880)
$134,583 median income
- 20851
Rockville (20851)
$126,411 median income
- 20850
Rockville (20850)
$125,950 median income
What this shows By household income, ZIP 20851 ranks #8 of 9 neighboring ZIPs, local affluence varies block to block, not just metro to metro.
| ZIP Code | City | Population | Distance |
|---|---|---|---|
| 20852 | Rockville, MD | 40,365 | 1.9 mi |
| 20853 | Rockville, MD | 29,673 | 2.2 mi |
| 20855 | Derwood, MD | 14,295 | 4.1 mi |
| 20896 | Garrett Park, MD | 906 | 3.3 mi |
| 20850 | Rockville, MD | 46,340 | 3.3 mi |
| 20906 | Silver Spring, MD | 64,696 | 3.5 mi |
| 20814 | Bethesda, MD | 27,642 | 5.2 mi |
| 20895 | Kensington, MD | 19,054 | 4.3 mi |
| 20817 | Bethesda, MD | 36,240 | 5.7 mi |
| 20880 | Washington Grove, MD | 450 | 5.1 mi |
Nationwide ZIPs with similar ACS profiles
Two Census-derived peer sets for ZIP 20851, both outside MD so the neighborhoods are not geographic containment (Nearby and same-county blocks stay local).
Similar population
Nearest cross-state ZIPs by resident population (14,191 here; floor ≥1,000).
Similar median household income
Nearest cross-state ZIPs by ACS median household income.
More ZIP Codes in Montgomery County
Related Areas
Frequently Asked Questions
What county is ZIP code 20851 in?
ZIP code 20851 (Rockville) is located in Montgomery County, Maryland. Montgomery County contains multiple ZIP codes, see the full list at /counties/montgomery-md.
What is the population of ZIP code 20851?
ZIP code 20851 in Rockville, MD has a population of 14,191 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 20851?
The median household income in ZIP 20851 is $126,411, which is 66% above the national average of $76,288.
What is the average home value in ZIP 20851?
The median home value in ZIP 20851 is $568,900, which is 105% above the national average of $278,155.
What is the demographic makeup of ZIP 20851?
The largest racial group in ZIP 20851 is White at 30.7%. Hispanic or Latino residents make up 44.1% of the population.
How many businesses are in ZIP code 20851?
ZIP code 20851 has 168 business establishments employing approximately 1,180 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 20851?
The top industries by establishment count in ZIP 20851 are: Construction (32), Other services (except public administration) (23), Retail trade (22). There are 11 industry sectors represented in total.
How have home values changed in ZIP code 20851?
According to the FHFA House Price Index, home values in ZIP 20851 increased by 5.1% in 2024. Since 2000, home values in this ZIP have appreciated by approximately 219%. This is a developmental index based on repeat sales and appraisal data from Fannie Mae and Freddie Mac.
What is the education level in ZIP code 20851?
In ZIP code 20851, 65.9% of residents aged 25+ have a high school diploma or higher, and 46.2% hold a bachelor's degree or higher. These figures come from the Census Bureau ACS 5-Year Estimates (2023).
What is the average commute time in ZIP 20851?
The mean commute time for workers in ZIP code 20851 is 31.8 minutes according to Census ACS data. The national average is roughly 26 minutes, so commuters here spend more time traveling to work than typical.
What percentage of residents own vs. rent in ZIP 20851?
In ZIP code 20851, approximately 57.5% of occupied housing units are owner-occupied and 42.5% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 20851?
The poverty rate in ZIP code 20851 is 9.1% according to Census Bureau ACS 2023 estimates. This measures the percentage of the population living below the federal poverty threshold.
Related
Take this with you
What to do with ZIP 20851's numbers, next.
- See how ZIP 20851 compares to a neighboring ZIP code on the same Census fields Compare this ZIP
- Check where Rockville, MD ranks among every U.S. ZIP code on income, education, or homeownership View national rankings
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ZIP Code Tabulation Areas (ZCTAs) are Census Bureau approximations of USPS ZIP codes; figures describe the ZCTA area, not any single address within it.