What city is 21904 in?

21904 is a Port Deposit, MD mailing address. By land area, 10% lies inside Port Deposit and 2% lies inside Perryville; the rest is outside any Census-defined city or community.

What is the population of 21904?

About 6,233 people (±716), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 6,689.

What is the median household income in 21904?

$88,136 (±$12,508), 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 21904?

6 USPS carrier routes with 2,738 residential and 76 business mailboxes (2,814 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.

What ZIP codes are near 21904?

The closest, measured center to center: 21903 (3.1 mi, Perryville), 21917 (4.2 mi), 21902 (4.4 mi), 21914 (5.2 mi, Charlestown), 21078 (5.5 mi, Havre de Grace) and 21901 (5.8 mi, North East).

21904 ZIP Code, Port Deposit, MD

21904 is a ZIP code in Port Deposit, Maryland in Cecil County. It covers 24 square miles of land. The closest ZIP codes are 21903, 21917 and 21902. 6,233 people live here in 2,269 households. With about 264 people per square mile it is lightly settled, and most homes are owner-occupied (89%). Median household income is $88,136, below the Maryland median of $103,678.

Quick facts

Mailing city: Port Deposit, MD
County: Cecil County
Land area: 24 sq mi
Population: 6,233
Median household income: $88,136
Carrier routes: 6 (2,738 homes)

Key figures

Measure	Value
Residents	6,233
Households	2,269
Median household income	$88,136
Income per person	$41,351
Median age	39.7
Homeowners	89.0%
Median home value	$333,500
Median rent	$1,422
Bachelor's degree or higher	28.0%
Average commute (minutes)	29.6
Households with kids under 18	37.3%
Moved in the past year	7.5%
Below the poverty line	7.7%
Broadband internet	94.8%
Speak a non-English language at home	3.7%

Household income

% of households	Value
<$10K	2.2%
$10–15K	3.7%
$15–25K	4.7%
$25–35K	9.4%
$35–50K	4.2%
$50–75K	15.5%
$75–100K	15.1%
$100–150K	17.7%
$150–200K	13.4%
$200K+	14.0%

Age

% of all residents	Value
<10	12.2%
10–19	13.0%
20–24	7.7%
25–34	7.6%
35–44	14.0%
45–54	15.0%
55–64	17.4%
65–74	7.9%
75+	5.3%

Tenure

% of housing units	Value
Owned, with mortgage	50.8%
Owned outright	26.8%
Rented	9.3%
Vacant	13.1%

Type of building

% of housing units	Value
Detached house	65.3%
Townhome	2.5%
2–4 units	4.0%
5–19 units	4.9%
20+ units	1.6%
Mobile / other	21.5%

Businesses in 21904

78 business establishments with 513 employees (ZIP Codes Business Patterns 2023).

Construction: 14
Accommodation and Food Services: 10
Other Services (except Public Administration): 10
Retail Trade: 7
Real Estate and Rental and Leasing: 7
Professional, Scientific, and Technical Services: 7
Wholesale Trade: 5
Transportation and Warehousing: 4

EDDM carrier routes

21904 has 6 USPS carrier routes with 2,738 residential and 76 business mailboxes. Open the EDDM route map.

Carrier routes in 21904

21904 has 6 USPS carrier routes (1 city (C), 5 rural (R)) with 2,738 residential and 76 business mailboxes. Routes range from 243 homes (R005) to 560 homes (R003); the median route has 511 homes. The Census counted 2,269 households in 21904 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.

Homes per route	Routes
1–249	1
250–499	1
500–749	4
750–999	0
1,000–1,499	0
1,500+	0

Best routes in 21904 for…

Most businesses

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

Route R001 — USPS business mailboxes 24, 533 homes
Route C001 — USPS business mailboxes 19, 380 homes
Route R002 — USPS business mailboxes 17, 516 homes
Route R003 — USPS business mailboxes 10, 560 homes
Route R004 — USPS business mailboxes 5, 506 homes

Select these 5 routes on the route map

Every carrier route in 21904

Route	Type	Homes	Businesses	Est. median income	Est. owners	Est. families with kids	Est. moved in past year
C001	City	380	19	$72,499	—	—	—
R001	Rural	533	24	$76,982	—	—	—
R002	Rural	516	17	$102,285	—	—	—
R003	Rural	560	10	$72,499	—	—	—
R004	Rural	506	5	$72,499	—	—	—
R005	Rural	243	1	$95,922	—	—	—

Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 21904 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

21903 — Perryville town, MD (3.1 mi)
21917 (4.2 mi)
21902 (4.4 mi)
21914 — Charlestown town, MD (5.2 mi)
21078 — Havre de Grace city, MD (5.5 mi)
21901 — North East town, MD (5.8 mi)
21911 — Rising Sun town, MD (5.8 mi)
21918 (7.2 mi)

Areas that include 21904

Where it ranks

Mail every home in 21904

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) 21904, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.

Frequently asked questions

What city is 21904 in?: 21904 is a Port Deposit, MD mailing address. By land area, 10% lies inside Port Deposit and 2% lies inside Perryville; the rest is outside any Census-defined city or community.
What county is 21904 in?: 21904 is in Cecil County.
What is the population of 21904?: About 6,233 people (±716), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 6,689.
What is the median household income in 21904?: $88,136 (±$12,508), 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 21904?: 6 USPS carrier routes with 2,738 residential and 76 business mailboxes (2,814 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
What ZIP codes are near 21904?: The closest, measured center to center: 21903 (3.1 mi, Perryville), 21917 (4.2 mi), 21902 (4.4 mi), 21914 (5.2 mi, Charlestown), 21078 (5.5 mi, Havre de Grace) and 21901 (5.8 mi, North East).

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