20606 ZIP Code, St. Mary's County, MD

20606 is a ZIP code in St. Mary's County, Maryland in St. Mary's County. It covers 0.9 square miles of land. The closest ZIP codes are 20609, 20626 and 20618. 291 people live here in 131 households, fewer than in most Maryland ZIP codes. With about 320 people per square mile it is lightly settled, and most homes are owner-occupied (85%). Median household income is $88,262, below the Maryland median of $103,678; the median age is 56.5, older than most ZIP codes.

Quick facts

Key figures

MeasureValue
Residents291
Households131
Median household income$88,262
Income per person$53,908
Median age56.5
Homeowners84.7%
Median home value$451,000
Median rentnot published
Bachelor's degree or higher29.8%
Average commute (minutes)52.6
Households with kids under 1811.5%
Moved in the past year4.8%
Below the poverty line0.0%
Broadband internet84.7%
Speak a non-English language at home0.0%

Household income

% of householdsValue
<$10K0.0%
$10–15K0.0%
$15–25K0.0%
$25–35K0.0%
$35–50K0.0%
$50–75K15.3%
$75–100K56.5%
$100–150K0.0%
$150–200K22.9%
$200K+5.3%

Age

% of all residentsValue
<100.0%
10–1921.7%
20–240.0%
25–340.0%
35–445.8%
45–5419.2%
55–6437.8%
65–7410.0%
75+5.5%

Tenure

% of housing unitsValue
Owned, with mortgage39.5%
Owned outright20.5%
Rented10.8%
Vacant29.2%

Type of building

% of housing unitsValue
Detached house89.2%
Townhome0.0%
2–4 units10.8%
5–19 units0.0%
20+ units0.0%
Mobile / other0.0%

EDDM carrier routes

20606 has 1 USPS carrier routes with 157 residential and 0 business mailboxes. Open the EDDM route map.

Carrier routes in 20606

20606 has 1 USPS carrier routes (1 highway contract (H)) with 157 residential and 0 business mailboxes. Routes range from 157 homes (H062) to 157 homes (H062); the median route has 157 homes. The Census counted 131 households in 20606 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.

Homes per routeRoutes
1–2491
250–4990
500–7490
750–9990
1,000–1,4990
1,500+0

Every carrier route in 20606

RouteTypeHomesBusinessesEst. median incomeEst. ownersEst. families with kidsEst. moved in past year
H062Highway contract1570$83,724———

Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 20606 on the EDDM route map.

How route demographics are estimated

Mailbox counts come from USPS; demographics are estimates

The number of homes and businesses on each carrier route is the current USPS EDDM count. The Census Bureau does not publish figures for carrier routes, so income, homeownership, ages, families, movers and housing age on a route are EDDM2GO estimates built from Census block groups (neighborhood areas of roughly 600 to 3,000 people).

How a route gets its figures: the block-group length-share method

We trace each route's streets every 25 meters and record which block group each stretch falls in. The route's homes are spread along its streets in proportion to length, so a route with 60% of its street length in one block group is assumed to have 60% of its homes there. Each block group then contributes its Census counts in proportion to the share of its housing units that sit on the route (capped at the whole block group). Medians are recalculated from the combined income, home-value and age brackets, the way the Census Bureau computes them, not averaged.

Margins of error

Census survey figures carry a margin of error at 90% confidence; we carry it through the calculation and show it as ±. Our margins treat the route-to-block-group split as exact, so the real uncertainty is larger. Routes with fewer than 100 estimated households, large margins, or streets we could not place are flagged.

Different years

USPS mailbox counts are current. Census figures are 5-year averages for 2020–2024, so a new subdivision may have more homes on the route today than the Census counted. Use the route figures to compare routes with each other, not as an exact head count.

Why some routes show identical figures

Two routes that run through the same block group get the same percentages and medians, because the Census publishes one set of figures for the whole block group. Their mailbox counts still differ, and those are exact.

Route and mailbox counts: USPS EDDM route data. Route demographics: EDDM2GO estimates from U.S. Census Bureau American Community Survey 5-year block-group data (2020–2024) and 2024 cartographic block-group boundaries. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.

Nearby ZIP codes

Areas that include 20606

Mail every home in 20606

Route counts on this page price as Full Service 6.5 × 9 postcards: we print, bundle by carrier route and hand the mailing to USPS. Prefer to take it to the Post Office yourself? Print only costs less and you pay postage at drop-off.

EDDM guides

ZIP code statistics describe the Census ZIP Code Tabulation Area (ZCTA) 20606, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.

Frequently asked questions

What city is 20606 in?
20606 is a St. Mary's County, MD mailing address. None of its land lies inside a Census-defined city or community.
What county is 20606 in?
20606 is in St. Mary's County.
What is the population of 20606?
About 291 people (±190), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 251.
What is the median household income in 20606?
$88,262 (±$14,678), compared with $103,678 for Maryland as a whole. Half the households in the ZIP code earn more and half earn less.
How many carrier routes and mailboxes are in 20606?
1 USPS carrier routes with 157 residential and 0 business mailboxes (157 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
What ZIP codes are near 20606?
The closest, measured center to center: 20609 (1.6 mi), 20626 (1.8 mi), 20618 (3.3 mi), 20625 (5.5 mi, Cobb Island), 20624 (5.6 mi) and 20621 (5.7 mi).

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.