Mechanicsville, MD · standard
ZIP Code 20659
St. Mary's County, Maryland - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.
- 23,498
- 97/sq mi Moderate-density area
- $121,654
- Median income Above-median income area
- $416,900
- Median home value Above-median home value
- 27.5%
- Bachelor's or higher Near-average bachelor's attainment
National ZIP placement
Mechanicsville pairs a top-decile household income with upper-quartile home values, in a rural, homeowner-dominated area.
- Top 9%
- household income, US ZIPs
- Top 19%
- home value, US ZIPs
- 97
- people per sq mi
- 89%
- owner-occupied homes
Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 20659 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 20659 (Mechanicsville, MD) rose +6.5% from 2023 to 2024. The all-transactions index moved from 222.6 in 2023 to 237.0 in 2024 (2000 = 100).
ZIP code 20659 is a densely settled ZIP (a standard USPS delivery area) in Mechanicsville, St. Mary's County, Maryland, with 23,498 residents across 243.5 square miles, a density of 97 people per square mile, in the New York time zone.
ZIP 20659 skews affluent, with a median household income of $121,654 (7% above the average Maryland ZIP), while per-capita income is $51,368. Both reported hardship measures are comparatively low in absolute terms: poverty is 7.5% and unemployment is 2.7%. Median home value is $416,900 (7% below the average Maryland ZIP) and median rent is $1,527; 88.6% of occupied homes are owner-occupied.
Educational attainment sits below the national norm: 27.5% of adults hold a bachelor's degree or higher, the median age is 37.5, and the average commute is 41 minutes. The page also surfaces 10 ZIP codes within roughly 10 miles and 6 more in St. Mary's County, so 20659 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 20659
Top 5 sectors by establishment count in Mechanicsville, MD
Which industries have the most business establishments in ZIP 20659.
- Construction
Construction
97 establishments
- Retail trade
Retail trade
39 establishments
- Other services (except public administration) 30
Other services (except public administration)
30 establishments
- Professional, scientific, and technical services 27
Professional, scientific, and technical services
27 establishments
- Administrative and support and waste management and remediation services 26
Administrative and support and waste management and remediation services
26 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 20659, Mechanicsville, 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
23,498
Population
243.5
Area (sq mi)
97
People / sq mi
New York
Time Zone
standard
ZIP Type
Who lives in ZIP 20659?
37.5
Median Age
50.1%
Male
49.9%
Female
2.7%
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?
$121,654
Median Household Income
+7% vs state ZIP avg
$51,368
Per Capita Income
7.5%
Poverty Rate
2.7%
Unemployment Rate
40.8 min
Mean Commute Time
How ZIP 20659 ranks among Maryland ZIPs
Mechanicsville, 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)
$121,654 Top 38% higher than 62% 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
8,633housing units
8,633
Total Housing Units
8,300
Occupied Units
333
Vacant Units
2.93
Avg Household Size
Occupancy Type
$416,900
Median Home Value
-7% vs state ZIP avg
$1,527
Median Rent
1988
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
+6.5%
YoY Change (2024)
237
HPI Index (2000 = 100)
+137%
Total Change Since 2000
Home values in ZIP 20659 have increased 6.5% over the past year (2024). Since 2000, this ZIP has seen +137% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2020 | +2.4% | 180 |
| 2021 | +9.1% | 197 |
| 2022 | +9.7% | 216 |
| 2023 | +3.3% | 223 |
| 2024 | +6.5% | 237 |
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 328 business establishments in ZIP 20659, employing approximately 1,996 people with a combined annual payroll of $99,819,000.
328
Businesses
1,996
Employees
$99.8M
Annual Payroll
16
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Construction | 97 | 29.6% |
| Retail trade | 39 | 11.9% |
| Other services (except public administration) | 30 | 9.2% |
| Professional, scientific, and technical services | 27 | 8.2% |
| Administrative and support and waste management and remediation services | 26 | 7.9% |
| Health care and social assistance | 25 | 7.6% |
| Transportation and warehousing | 23 | 7.0% |
| Accommodation and food services | 13 | 4.0% |
| Real estate and rental and leasing | 10 | 3.0% |
| Wholesale trade | 9 | 2.7% |
| Finance and insurance | 8 | 2.4% |
| Arts, entertainment, and recreation | 6 | 1.8% |
| Information | 5 | 1.5% |
| Agriculture, forestry, fishing and hunting | 3 | 0.9% |
| Manufacturing | 3 | 0.9% |
| Educational services | 3 | 0.9% |
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 20659 vs 20660 →
ZIP 20659 vs its nearest neighbors, by population
Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 20659
Mechanicsville (20659)
23,498 residents
- 20678
Prince Frederick (20678)
11,045 residents
- 20637 5,423
Hughesville (20637)
5,423 residents
- 20622 4,900
Charlotte Hall (20622)
4,900 residents
- 20621 1,373
Chaptico (20621)
1,373 residents
- 20624 1,282
Clements (20624)
1,282 residents
- 20609 1,120
Avenue (20609)
1,120 residents
- 20617 781
Bryantown (20617)
781 residents
- 20618 607
Bushwood (20618)
607 residents
What this shows Among its immediate neighbors, ZIP 20659 ranks the most populous - useful context the national average alone can't give.
ZIP 20659 vs its nearest neighbors, by median income
Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 20637
Hughesville (20637)
$160,121 median income
- 20678
Prince Frederick (20678)
$125,732 median income
- 20622
Charlotte Hall (20622)
$124,063 median income
- 20659
Mechanicsville (20659)
$121,654 median income
- 20609
Avenue (20609)
$118,102 median income
- 20618
Bushwood (20618)
$105,508 median income
- 20624
Clements (20624)
$104,545 median income
- 20617
Bryantown (20617)
$104,036 median income
- 20612 $41,118
Benedict (20612)
$41,118 median income
What this shows By household income, ZIP 20659 ranks #4 of 9 neighboring ZIPs, local affluence varies block to block, not just metro to metro.
| ZIP Code | City | Population | Distance |
|---|---|---|---|
| 20660 | Morganza, MD | 97 | 3.7 mi |
| 20624 | Clements, MD | 1,282 | 5.8 mi |
| 20612 | Benedict, MD | 261 | 6.6 mi |
| 20622 | Charlotte Hall, MD | 4,900 | 6.6 mi |
| 20637 | Hughesville, MD | 5,423 | 7.7 mi |
| 20621 | Chaptico, MD | 1,373 | 7.1 mi |
| 20609 | Avenue, MD | 1,120 | 10.2 mi |
| 20618 | Bushwood, MD | 607 | 10.1 mi |
| 20678 | Prince Frederick, MD | 11,045 | 9.8 mi |
| 20617 | Bryantown, MD | 781 | 10.6 mi |
Nationwide ZIPs with similar ACS profiles
Two Census-derived peer sets for ZIP 20659, 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 (23,498 here; floor ≥1,000).
Similar median household income
Nearest cross-state ZIPs by ACS median household income.
More ZIP Codes in St. Mary's County
Related Areas
Frequently Asked Questions
What county is ZIP code 20659 in?
ZIP code 20659 (Mechanicsville) is located in St. Mary's County, Maryland. St. Mary's County contains multiple ZIP codes, see the full list at /counties/st-marys-md.
What is the population of ZIP code 20659?
ZIP code 20659 in Mechanicsville, MD has a population of 23,498 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 20659?
The median household income in ZIP 20659 is $121,654, which is 59% above the national average of $76,288.
What is the average home value in ZIP 20659?
The median home value in ZIP 20659 is $416,900, which is 50% above the national average of $278,155.
What is the demographic makeup of ZIP 20659?
The largest racial group in ZIP 20659 is White at 86.2%. Hispanic or Latino residents make up 3.1% of the population.
How many businesses are in ZIP code 20659?
ZIP code 20659 has 328 business establishments employing approximately 1,996 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 20659?
The top industries by establishment count in ZIP 20659 are: Construction (97), Retail trade (39), Other services (except public administration) (30). There are 16 industry sectors represented in total.
How have home values changed in ZIP code 20659?
According to the FHFA House Price Index, home values in ZIP 20659 increased by 6.5% in 2024. Since 2000, home values in this ZIP have appreciated by approximately 137%. 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 20659?
In ZIP code 20659, 59.7% of residents aged 25+ have a high school diploma or higher, and 27.5% 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 20659?
The mean commute time for workers in ZIP code 20659 is 40.8 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 20659?
In ZIP code 20659, approximately 88.6% of occupied housing units are owner-occupied and 11.4% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 20659?
The poverty rate in ZIP code 20659 is 7.5% 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 20659's numbers, next.
- See how ZIP 20659 compares to a neighboring ZIP code on the same Census fields Compare this ZIP
- Check where Mechanicsville, MD ranks among every U.S. ZIP code on income, education, or homeownership View national rankings
- Save this ZIP to your shortlist to track alongside others you're considering View your shortlist
ZIP Code Tabulation Areas (ZCTAs) are Census Bureau approximations of USPS ZIP codes; figures describe the ZCTA area, not any single address within it.