🇺🇸 United States ZIP Code

STANDARD

21661

Rock Hall

ZIP Code 21661 is a standard zip code serving Rock Hall, Rock Hall, Maryland (MD), in Kent County, United States. It has an estimated population of 2,653 with a median household income of $48,594. The area falls within the America/New_York timezone.

Median Household Income vs. National Average

Location

Country: 🇺🇸 United States
State / Province: Maryland (MD)
County: Kent
City: Rock Hall
Timezone: America/New_York

Coordinates

Latitude: 39.134400
Longitude: -76.230500

Geographic Details

Land Area: 32.42 mi²
Water Area: 21.99 mi²
Population Density: 82.0 people per mi² (50th percentile)
Bounding Box: 39.215272°N, 38.992428°S, -76.166592°E, -76.285882°W

With 2,653 residents spread across 32.42 square miles, this area has a population density of 82.0 people per square mile.

Demographics

2,653

Population

45th percentile

$48,594

Median Income

50th percentile

$283,500

Median Home Value

85th percentile

32.42 mi²

Land Area

The median household income in 21661 is $48,594, and the median home value is $283,500.

Housing

1,792

Total Units

1,226

Occupied Units

68.4%

Occupancy Rate

Similar ZIP Codes in Maryland

ZIP codes with similar median household income in Maryland.

21645

Kennedyville

$44,844

21640

Henderson

$47,778

21643

Hurlock

$54,662

21869

Vienna

$51,833

21221

Essex

$52,355

21919

Earleville

$49,038

21545

Mount Savage

$49,222

21850

Pittsville

$54,103

Frequently Asked Questions

What information is available for each ZIP code?

Each ZIP code page shows city, state, county, geographic coordinates, timezone, population, median household income, median home value, housing units, land area, population density, commute time, educational attainment, area codes, and ZIP code type (Standard, PO Box, or Unique).

What are the different types of ZIP codes?

There are three types of ZIP codes: Standard (residential and commercial delivery areas), PO Box (assigned to post office box sections), and Unique (assigned to a single high-volume address like a government agency or large company). Standard ZIP codes are the most common.

How often is ZIP code data updated?

ZIP code assignments are updated quarterly by the USPS. Demographic data comes from the US Census Bureau's American Community Survey (ACS), which releases new 5-year estimates annually. ZipFYI updates its data to reflect the latest available information.

What is population density and why does it matter?

Population density measures the number of people per square mile in a ZIP code area. It helps identify urban vs. rural areas, affects real estate values, impacts service availability, and is used in market analysis. Dense urban ZIP codes may have 50,000+ people per square mile.

How are ZIP code boundaries determined?

ZIP code boundaries are determined by the USPS based on mail delivery routes, not political or geographic boundaries. They follow carrier routes and may cross city, county, or even state lines. Boundaries can change when the USPS reorganizes delivery operations.

What does median household income tell me about a ZIP code?

Median household income is the middle value when all household incomes in a ZIP code are sorted. Half of households earn more and half earn less. It is a better indicator of typical earnings than average income, which can be skewed by very high or very low outliers.