ZIP Code Tabulation Area · Maryland

ZIP Code 20621: St. Mary's County, MD

ZIP Code 20621 (St. Mary's County, Maryland) has an estimated 958 residents in 534 households. The median household income is —, the median home value is $481,100 and the median gross rent is —. Figures are U.S. Census Bureau American Community Survey 2020–2024 5-year estimates for the matching ZIP Code Tabulation Area.

American Community Survey 2020–2024 5-year estimates · Updated

Some estimates have a large margin of error. 3 figures for this ZIP (poverty rate, unemployment, commute) are marked with *. ACS figures come from a sample, and small areas have fewer responses, so treat these numbers as rough ranges.

Total population

958

Margin of error ±345

Median household income

—

Margin of error not available

Median home value

$481,100

Margin of error ±$182,100

Median gross rent

—

Margin of error not available

Median age

63.0 yrs

Margin of error ±9.1 yrs

Mean travel time to work

45.3 min*

Margin of error ±30.8 min· estimate has a large margin of error

How ZIP 20621 compares with Maryland and the U.S.

State and national figures are the Census Bureau's own estimates for those areas from the same ACS release, not averages of ZIP codes.

Median age

ZIP 2062163.0 yrsMaryland39.4 yrsUnited States38.9 yrs

Median household income

ZIP 20621—Maryland$103,678United States$80,734

Per capita income

ZIP 20621$54,408Maryland$52,979United States$44,673

Poverty rate

ZIP 2062120.0%*Maryland9.4%United States12.5%

Unemployment rate

ZIP 2062114.4%*Maryland4.9%United States5.2%

Bachelor's degree or higher

ZIP 2062115.8%Maryland43.4%United States35.7%

Median home value

ZIP 20621$481,100Maryland$419,900United States$332,700

Median gross rent

ZIP 20621—Maryland$1,705/moUnited States$1,413/mo

Owner-occupied homes

ZIP 20621100.0%Maryland67.6%United States65.2%

Mean travel time to work

ZIP 2062145.3 min*Maryland31.1 minUnited States26.4 min

Worked from home

ZIP 206214.4%Maryland19.3%United States15.1%

All figures for ZIP 20621

Each estimate has a 90% margin of error: the true value is likely within that range. * marks estimates with a large margin of error (a coefficient of variation above 30%, or ±10 percentage points or more for rates).

ZIP 20621 — ACS 2020–2024 5-year estimates
MeasureZIP 20621Margin of errorMarylandUnited States
Total population958±3456,206,011334,922,499
Median age63.0 yrs±9.1 yrs39.4 yrs38.9 yrs
Households534±2432,362,928129,227,496
Median household income——$103,678$80,734
Per capita income$54,408±$16,469$52,979$44,673
Poverty rate20.0%*±19.0 pts9.4%12.5%
Unemployment rate14.4%*±15.2 pts4.9%5.2%
Bachelor's degree or higher15.8%±8.6 pts43.4%35.7%
Median home value$481,100±$182,100$419,900$332,700
Median gross rent——$1,705/mo$1,413/mo
Owner-occupied homes100.0%±0.0 pts67.6%65.2%
Mean travel time to work45.3 min*±30.8 min31.1 min26.4 min
Worked from home4.4%±4.2 pts19.3%15.1%

Race and Hispanic or Latino origin

Shares of the total population by the Census Bureau's race and Hispanic or Latino origin categories (table B03002), listed in the Census Bureau's order. People self-identify on the survey.

Population by race and Hispanic or Latino origin, ZIP 20621
GroupZIP 20621MarylandUnited States
White alone, not Hispanic or Latino77.0%46.6%57.4%
Black or African American alone, not Hispanic or Latino23.0%28.9%11.9%
American Indian and Alaska Native alone, not Hispanic or Latino0.0%0.1%0.5%
Asian alone, not Hispanic or Latino0.0%6.5%5.9%
Native Hawaiian and Other Pacific Islander alone, not Hispanic or Latino0.0%0.0%0.2%
Some other race alone, not Hispanic or Latino0.0%0.7%0.6%
Two or more races, not Hispanic or Latino0.0%4.6%4.3%
Hispanic or Latino (of any race)0.0%12.5%19.3%

Where ZIP 20621 is

State
Maryland
Main county
St. Mary's County
Land area
13.86 sq mi· about 69 people per sq mi

County and place names come from the Census Bureau's 2020 ZCTA relationship files. A ZIP code's mailing city, set by the U.S. Postal Service, can differ from these names.

Other ZIP codes in St. Mary's County

20606 St. Mary's County, MD20609 St. Mary's County, MD20618 St. Mary's County, MD20619 California, MD20620 Callaway, MD20624 St. Mary's County, MD20626 St. Mary's County, MD20628 St. Mary's County, MD20630 St. Mary's County, MD20634 California, MD20636 St. Mary's County, MD20650 St. Mary's County, MD20653 St. Mary's County, MD20656 St. Mary's County, MD20659 St. Mary's County, MD20667 St. Mary's County, MD20670 St. Mary's County, MD20674 Piney Point, MD20680 St. Mary's County, MD20684 St. Mary's County, MD20686 St. Mary's County, MD20687 St. Mary's County, MD20690 Tall Timbers, MD20692 St. Mary's County, MD

See every ZIP code in Maryland, or compare ZIP 20621 with another ZIP code.

Census figures describe residents as a group and cannot tell you about any one home or street. For a specific address, check local government and housing records.

About ZIP codes and ZCTAs: the Census Bureau publishes statistics for ZIP Code Tabulation Areas, which approximate USPS ZIP code delivery areas. Learn how they differ.

Sources

  • U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, detailed tables B01003, B01002, B11001, B19013, B19301, B17001, B23025, B15003, B25077, B25064, B25003, B08013, B08303, B08301, B03002 — snapshot Oct 26, 2026.
  • U.S. Census Bureau, 2020 ZCTA5 relationship files (county and place).
  • Data: U.S. Census Bureau, American Community Survey 5-year estimates (detailed tables) and 2020 Census ZCTA relationship files. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau. These agencies do not endorse OpenZIP.