What city is 21655 in?

21655 is a Preston, MD mailing address. By land area, 1% lies inside Preston; the rest is outside any Census-defined city or community.

What is the population of 21655?

About 5,053 people (±497), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 4,798.

What is the median household income in 21655?

$90,385 (±$18,180), 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 21655?

3 USPS carrier routes with 1,950 residential and 51 business mailboxes (2,001 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.

What ZIP codes are near 21655?

The closest, measured center to center: 21643 (7.2 mi, Hurlock), 21632 (7.6 mi, Federalsburg), 21625 (9 mi, Cordova), 21629 (9.2 mi, Denton), 21664 (9.7 mi, Secretary) and 21601 (10 mi, Easton).

21655 ZIP Code, Preston, MD

21655 is a ZIP code in Preston, Maryland in Caroline County. It covers 53 square miles of land. The closest ZIP codes are 21643, 21632 and 21625. 5,053 people live here in 1,862 households. It is rural, with fewer than 100 people per square mile, and most homes are owner-occupied (84%). Median household income is $90,385, below the Maryland median of $103,678.

Quick facts

Mailing city: Preston, MD
County: Caroline County
Land area: 53 sq mi
Population: 5,053
Median household income: $90,385
Carrier routes: 3 (1,950 homes)

Key figures

Measure	Value
Residents	5,053
Households	1,862
Median household income	$90,385
Income per person	$42,506
Median age	42.2
Homeowners	84.0%
Median home value	$289,200
Median rent	$1,380
Bachelor's degree or higher	24.0%
Average commute (minutes)	29.2
Households with kids under 18	31.7%
Moved in the past year	5.8%
Below the poverty line	4.3%
Broadband internet	92.1%
Speak a non-English language at home	2.0%

Household income

% of households	Value
<$10K	2.8%
$10–15K	0.7%
$15–25K	3.7%
$25–35K	3.9%
$35–50K	14.4%
$50–75K	16.5%
$75–100K	15.0%
$100–150K	23.4%
$150–200K	11.9%
$200K+	7.5%

Age

% of all residents	Value
<10	12.6%
10–19	10.2%
20–24	7.3%
25–34	10.4%
35–44	14.8%
45–54	11.5%
55–64	14.4%
65–74	11.3%
75+	7.3%

Tenure

% of housing units	Value
Owned, with mortgage	46.8%
Owned outright	32.1%
Rented	14.8%
Vacant	6.3%

Type of building

% of housing units	Value
Detached house	93.2%
Townhome	0.1%
2–4 units	1.9%
5–19 units	0.6%
20+ units	0.0%
Mobile / other	4.3%

Businesses in 21655

91 business establishments with 614 employees (ZIP Codes Business Patterns 2023).

Construction: 21
Professional, Scientific, and Technical Services: 12
Administrative and Support and Waste Management and Remediation Services: 12
Other Services (except Public Administration): 12
Retail Trade: 10
Transportation and Warehousing: 6
Health Care and Social Assistance: 4
Wholesale Trade: 3

EDDM carrier routes

21655 has 3 USPS carrier routes with 1,950 residential and 51 business mailboxes. Open the EDDM route map.

Carrier routes in 21655

21655 has 3 USPS carrier routes (3 rural (R)) with 1,950 residential and 51 business mailboxes. Routes range from 623 homes (R003) to 690 homes (R002); the median route has 637 homes. The Census counted 1,862 households in 21655 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.

Homes per route	Routes
1–249	0
250–499	0
500–749	3
750–999	0
1,000–1,499	0
1,500+	0

Best routes in 21655 for…

Most businesses

For B2B offers: office supplies, cleaning, IT, catering and commercial services.

Route R003 — USPS business mailboxes 20, 623 homes
Route R001 — USPS business mailboxes 16, 637 homes
Route R002 — USPS business mailboxes 15, 690 homes

Select these 3 routes on the route map

Every carrier route in 21655

Route	Type	Homes	Businesses	Est. median income	Est. owners	Est. families with kids	Est. moved in past year
R001	Rural	637	16	$76,278	—	—	—
R002	Rural	690	15	$58,745	—	—	—
R003	Rural	623	20	$77,142	—	—	—

Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 21655 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

21643 — Hurlock town, MD (7.2 mi)
21632 — Federalsburg town, MD (7.6 mi)
21625 — Cordova CDP, MD (9 mi)
21629 — Denton town, MD (9.2 mi)
21664 — Secretary town, MD (9.7 mi)
21601 — Easton town, MD (10 mi)
21673 — Trappe town, MD (10 mi)
21631 — East New Market town, MD (11.3 mi)

Areas that include 21655

Where it ranks

Mail every home in 21655

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) 21655, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.

Frequently asked questions

What city is 21655 in?: 21655 is a Preston, MD mailing address. By land area, 1% lies inside Preston; the rest is outside any Census-defined city or community.
What county is 21655 in?: 21655 is in Caroline County.
What is the population of 21655?: About 5,053 people (±497), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 4,798.
What is the median household income in 21655?: $90,385 (±$18,180), 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 21655?: 3 USPS carrier routes with 1,950 residential and 51 business mailboxes (2,001 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
What ZIP codes are near 21655?: The closest, measured center to center: 21643 (7.2 mi, Hurlock), 21632 (7.6 mi, Federalsburg), 21625 (9 mi, Cordova), 21629 (9.2 mi, Denton), 21664 (9.7 mi, Secretary) and 21601 (10 mi, Easton).

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