ZIP Code 20634 · Great Mills, MD
St. Mary's County · pop 7,088 · ACS 2020–2024
The median household income in ZIP Code 20634 (Great Mills, MD) is $139,375, higher than 75% of the other ZIP Codes in Maryland.
Its FHFA home price index changed +56.9% over the five years to 2025.
01 — Where it stands
| Measure | Value | County percentile | State percentile | U.S. percentile |
|---|---|---|---|---|
| Median household income | $139,375 ± $17,358 | 66th percentile (10 ZIP Codes compared) | 75th percentile (347 ZIP Codes compared) | 94th percentile (22,922 ZIP Codes compared) |
| Per capita income | $61,800 | 100th percentile (10 ZIP Codes compared) | 76th percentile (347 ZIP Codes compared) | 89th percentile (22,922 ZIP Codes compared) |
| Poverty rate | 4.7% | 44th percentile (10 ZIP Codes compared) | 32nd percentile (347 ZIP Codes compared) | 12th percentile (22,922 ZIP Codes compared) |
| Adults with a bachelor’s degree or higher | 40.3% | 77th percentile (10 ZIP Codes compared) | 53rd percentile (347 ZIP Codes compared) | 76th percentile (22,922 ZIP Codes compared) |
| Owner-occupied homes | 65.4% | 33rd percentile (10 ZIP Codes compared) | 26th percentile (347 ZIP Codes compared) | 25th percentile (22,922 ZIP Codes compared) |
| Housing vacancy rate | 11.0% | 44th percentile (10 ZIP Codes compared) | 81st percentile (347 ZIP Codes compared) | 56th percentile (22,922 ZIP Codes compared) |
| Median home value | $342,300 ± $24,952 | 0th percentile (10 ZIP Codes compared) | 28th percentile (344 ZIP Codes compared) | 68th percentile (22,833 ZIP Codes compared) |
| Median gross rent | $1,814 | 66th percentile (10 ZIP Codes compared) | 64th percentile (345 ZIP Codes compared) | 85th percentile (22,865 ZIP Codes compared) |
| Income inequality (Gini index) | 0.380 | 44th percentile (10 ZIP Codes compared) | 26th percentile (347 ZIP Codes compared) | 16th percentile (22,922 ZIP Codes compared) |
| Average adjusted gross income per return | $80,974 | 22nd percentile (10 ZIP Codes compared) | 42nd percentile (341 ZIP Codes compared) | 66th percentile (22,230 ZIP Codes compared) |
| Returns with AGI of $200,000 or more | 6.2% | 22nd percentile (10 ZIP Codes compared) | 42nd percentile (341 ZIP Codes compared) | 68th percentile (22,230 ZIP Codes compared) |
| Home price index, 5-year change | +56.9% | 100th percentile (9 ZIP Codes compared) | 89th percentile (334 ZIP Codes compared) | 63rd percentile (18,843 ZIP Codes compared) |
| Business establishments per 1,000 residents | 6.8 | 11th percentile (10 ZIP Codes compared) | 1st percentile (345 ZIP Codes compared) | 4th percentile (22,700 ZIP Codes compared) |
| Average annual pay per employee | $50,221 | 55th percentile (10 ZIP Codes compared) | 44th percentile (345 ZIP Codes compared) | 55th percentile (22,551 ZIP Codes compared) |
Percentile groups: St. Mary's County · Maryland · U.S. Hover a percentile for the number of ZIP Codes compared. MOE = 90% margin of error.
02 — Home prices
Home price index — ZIP Code 20634
FHFA ZIP Code index (2000 = 100) — annual, developmental, not seasonally adjusted.
Data table
| Year | Index | Annual change |
|---|---|---|
| 2000 | 100.0 | −3.7% |
| 2001 | 108.1 | +8.1% |
| 2002 | 117.5 | +8.7% |
| 2003 | 121.6 | +3.5% |
| 2004 | 150.2 | +23.5% |
| 2005 | 182.1 | +21.2% |
| 2006 | 196.8 | +8.1% |
| 2007 | 200.8 | +2.0% |
| 2008 | 194.4 | −3.2% |
| 2009 | 174.8 | −10.1% |
| 2010 | 162.6 | −7.0% |
| 2011 | 168.8 | +3.9% |
| 2012 | 159.3 | −5.6% |
| 2013 | 161.7 | +1.5% |
| 2014 | 145.7 | −9.9% |
| 2015 | 142.7 | −2.0% |
| 2016 | 147.6 | +3.4% |
| 2017 | 155.7 | +5.5% |
| 2018 | 154.6 | −0.7% |
| 2019 | 177.6 | +14.8% |
| 2020 | 172.0 | −3.1% |
| 2021 | 186.7 | +8.5% |
| 2022 | 212.2 | +13.7% |
| 2023 | 217.8 | +2.7% |
| 2024 | 226.9 | +4.2% |
| 2025 | 269.9 | +18.9% |
03 — Nearby ZIP Codes
| ZIP | Place | Distance | Median household income | Median home value | Poverty rate | 5-yr HPI change |
|---|---|---|---|---|---|---|
| 20634 | Great Mills, MD | this ZIP Code | $139,375 | $342,300 | 4.7% | +56.9% |
| 20620 | Callaway, MD | 1.4 mi | $165,972 | $391,300 | 4.9% | +15.5% |
| 20667 | Park Hall, MD | 3.3 mi | $102,232 | $390,766 | 35.3% | — |
| 20653 | Lexington Park, MD | 3.8 mi | $103,048 | $353,300 | 15.0% | +43.2% |
| 20619 | California, MD | 3.9 mi | $119,432 | $376,800 | 7.1% | +43.2% |
| 20692 | Valley Lee, MD | 4.2 mi | $201,250 | $468,000 | 0.2% | +26.2% |
| 20686 | Saint Marys City, MD | 5.2 mi | $124,429 | $442,500 | 20.6% | +51.9% |
Up to six nearest ZIP Code Tabulation Areas within 30 miles, by straight-line distance between Census center points (2024 Gazetteer).
04 — Business mix
| Sector | Establishments | Share of ZIP | U.S. share | Relative concentration |
|---|---|---|---|---|
| Construction | 11 | 22.9% | 9.6% | 2.4× |
| Retail trade | 8 | 16.7% | 12.4% | 1.3× |
| Other services | 8 | 16.7% | 9.5% | 1.8× |
| Administrative & support services | 7 | 14.6% | 5.3% | 2.8× |
| Health care & social assistance | 6 | 12.5% | 11.9% | 1.1× |
| Real estate & rental | 5 | 10.4% | 5.5% | 1.9× |
| Professional, scientific & technical services | 3 | 6.2% | 11.7% | 0.5× |
Counts are establishments (business locations), not jobs. Relative concentration = the sector’s share of establishments here divided by its share in the U.S. (1.0× = the same share). Average pay is shown only where at least 20 employees are reported. ZIP Code Business Patterns 2023.
05 — About this data
How percentiles are calculated
Percentiles compare this ZIP Code with other ZIP Codes in the same county, the same state and the whole country. Only ZIP Codes with their own American Community Survey estimate, a population of at least 1,000 and a published median household income are compared, and only those with a value for the measure. A percentile of 64th means the value is higher than 64% of the other ZIP Codes in that group (0 is the lowest value, 100 the highest); it describes the size of a number, not a judgment about the area. County and state percentiles are left blank when the group has fewer than 5 ZIP Codes. The number of ZIP Codes compared is shown with each percentile.
Census figures are published for ZIP Code Tabulation Areas, which approximate USPS ZIP Code delivery areas; values shown as — are not published or are suppressed by the source.
Use of this page
Area statistics only. These figures describe a ZIP Code area — not any person or household — and do not rate the area or the people who live there. CoverFi is not a consumer reporting agency; do not use this page to make decisions about credit, insurance, employment or housing.
Sources
- U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, ZIP Code Tabulation Areas. Estimates are survey-based and have margins of error.
- U.S. Census Bureau, ZIP Code Business Patterns 2023 (establishment counts by NAICS sector; employment and payroll totals).
- Federal Housing Finance Agency, House Price Index for five-digit ZIP Codes, census tracts and counties — annual, developmental, not seasonally adjusted.
- IRS Statistics of Income, Individual Income Tax ZIP Code Data, tax year 2022.
- U.S. Census Bureau, 2024 Gazetteer Files (ZCTA locations, used for nearby ZIP Codes).
- HUD USPS ZIP Code Crosswalk Files (ZIP-to-tract and ZIP-to-county assignment).
This product uses Census Bureau data but is not endorsed or certified by the Census Bureau. This product uses the HUD User Data API but is not endorsed or certified by HUD User. ZIP Code Tabulation Areas are Census approximations of USPS ZIP Code delivery areas and may not match them exactly. ZIP Code is a trademark of the United States Postal Service.