PlainZIP

Marriottsville, MD · standard

ZIP Code 21104

Carroll County, Maryland - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.

4,601
105/sq mi
$191,804
Median income
$680,200
Median home value
64.4%
Bachelor's or higher

The verdict

Marriottsville pairs a top-decile household income with top-decile home values, in a rural, homeowner-dominated area.

Top 1%
household income, US ZIPs
Top 7%
home value, US ZIPs
105
people per sq mi
97%
owner-occupied homes

Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 21104 against every reporting US ZIP.

ZIP code 21104 covers 44.0 square miles in Marriottsville, Carroll County, Maryland (a standard USPS delivery area), with a modest 4,601 residents on file, a density of 105 people per square mile, in the New York time zone.

ZIP 21104 skews affluent, with a median household income of $191,804 (68% above the Maryland average), while per-capita income is $74,405. 2.7% of residents live below the poverty line, and the unemployment rate reads 3.2%. Housing costs here run $680,200 for a typical home value (52% above the state average), with rent averaging $1,384 a month; 97.0% of homes are owner-occupied.

This is a highly-educated ZIP: 64.4% of adults hold a bachelor's degree or higher, the median age is 43.1, and the average commute is 32 minutes. We also surface 10 nearby ZIP codes within roughly 10 miles and 6 additional ZIPs sharing Carroll County, so you can benchmark 21104 against its immediate geography rather than a national average alone.

Every figure on this page is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates (including median rent) and the FHFA House Price Index, no estimates, no proprietary scoring. Verify with Census →

Top industries in ZIP 21104

Top 5 sectors by establishment count in Marriottsville, MD

Which industries have the most business establishments in ZIP 21104.

establishments

What this shows Establishment counts come from the Census ZIP Code Business Patterns program, which counts physical business locations rather than employees or revenue.

Source U.S. Census Bureau · ZIP Code Business Patterns (ZBP) As of 2023

Source: U.S. Census Bureau, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 21104, Marriottsville, MD · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; FHFA HPI updated quarterly/annually.

Quick Facts

4,601

Population

44.0

Area (sq mi)

105

People / sq mi

New York

Time Zone

standard

ZIP Type

Neighborhood Scorecard
Get an A-F grade across income, safety, housing, rent, education, commute, and childcare for this ZIP code.
View Scorecard →

Who lives in ZIP 21104?

43.1

Median Age

50.0%

Male

50.0%

Female

16.0%

Foreign-Born

White 75.5%
African American 5.9%
Asian 11.1%
American Indian or Alaska Native 0.0%
Native Hawaiian or Pacific Islander 0.0%
Two or More Ethnicities 4.8%
Hispanic or Latino 1.0%

Hispanic or Latino is an ethnicity category from the Census Bureau and may overlap with other categories above.

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

How much do residents earn?

$191,804

Median Household Income

+68% vs state

$74,405

Per Capita Income

2.7%

Poverty Rate

3.2%

Unemployment Rate

31.9 min

Mean Commute Time

How ZIP 21104 ranks nationally

Marriottsville, MD household income vs. every US ZIP code

Median household income, the full national distribution, with this ZIP marked

$191,804 Top 1% higher than 99% of 30,318 US ZIPs

$0–$20,000: 118 US ZIPs (0%). Below this entry. $20,000–$40,000: 1,573 US ZIPs (5%). Below this entry. $40,000–$60,000: 7,092 US ZIPs (23%). Below this entry. $60,000–$80,000: 9,980 US ZIPs (33%). Below this entry. $80,000–$100,000: 5,778 US ZIPs (19%). Below this entry. $100,000–$120,000: 2,855 US ZIPs (9%). Below this entry. $120,000–$140,000: 1,362 US ZIPs (4%). Below this entry. $140,000–$160,000: 686 US ZIPs (2%). Below this entry. $160,000–$180,000: 364 US ZIPs (1%). Below this entry. $180,000–$200,000: 186 US ZIPs (1%). This entry sits in this band. $200,000–$220,000: 324 US ZIPs (1%). Above this entry. This ZIP $0 $200K+ every reporting US ZIP, bucketed by value

Each bar is a $20K-wide band; taller bars hold more US ZIPs. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source U.S. Census Bureau, ACS 5-Year Estimates · 2019–2023

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

What is the education profile here?

High School Graduate or Higher 79.6%
Bachelor's Degree or Higher 64.4%

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

What does housing look like?

2,204

Total Housing Units

2,097

Occupied Units

107

Vacant Units

2.88

Avg Household Size

Occupancy Type

Owner 97.0%
Renter 3.0%

$680,200

Median Home Value

+52% vs state

$1,384

Median Rent

1995

Median Year Built

Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)

How have home values changed over time?

FHFA House Price Index, annual appreciation data based on repeat sales and appraisals

-3.1%

YoY Change (2024)

252

HPI Index (2000 = 100)

+152%

Total Change Since 2000

Home values in ZIP 21104 have decreased 3.1% over the past year (2024). Since 2000, this ZIP has seen +152% cumulative appreciation.

Year Annual Change HPI Index
2020 +5.5% 188
2021 +8.3% 203
2022 +13.9% 232
2023 +12.1% 260
2024 -3.1% 252

Source: Federal Housing Finance Agency (FHFA) House Price Index, All-Transactions, Five-Digit ZIP Codes (Developmental Index). Index base = 100 in year 2000. Data through 2024. ZIP codes with few transactions may show missing values.

What businesses operate in this ZIP?

Census Bureau data shows 157 business establishments in ZIP 21104, employing approximately 1,322 people with a combined annual payroll of $72,588,000.

157

Businesses

1,322

Employees

$72.6M

Annual Payroll

12

Industry Sectors

Industry Establishments % of Total
Professional, scientific, and technical services 40 25.5%
Construction 20 12.7%
Health care and social assistance 16 10.2%
Finance and insurance 11 7.0%
Administrative and support and waste management and remediation services 11 7.0%
Other services (except public administration) 11 7.0%
Real estate and rental and leasing 10 6.4%
Wholesale trade 9 5.7%
Accommodation and food services 9 5.7%
Arts, entertainment, and recreation 6 3.8%
Retail trade 4 2.5%
Transportation and warehousing 3 1.9%

Source: U.S. Census Bureau, ZIP Code Business Patterns (ZBP), 2023. Employment figures may include noise for disclosure avoidance.

Nearby ZIP Codes

Want a side-by-side? Compare 21104 vs 21163 →

ZIP 21104 vs its nearest neighbors, by population

Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.

residents

What this shows Among its immediate neighbors, ZIP 21104 ranks #8 by population - useful context the national average alone can't give.

Source U.S. Census Bureau · ACS 5-Year Estimates As of 2019–2023

ZIP 21104 vs its nearest neighbors, by median income

Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.

median income

What this shows By household income, ZIP 21104 ranks #4 of 9 neighboring ZIPs, local affluence varies block to block, not just metro to metro.

Source U.S. Census Bureau · ACS 5-Year Estimates As of 2019–2023
ZIP Code City Population Distance
21163 Woodstock, MD 7,026 2.8 mi
21042 Ellicott City, MD 38,076 5.5 mi
21784 Sykesville, MD 37,941 5.0 mi
21794 West Friendship, MD 2,434 5.1 mi
21133 Randallstown, MD 29,998 5.3 mi
21723 Cooksville, MD 803 5.8 mi
21244 Windsor Mill, MD 34,611 6.8 mi
21048 Finksburg, MD 10,650 10.1 mi
21044 Columbia, MD 41,704 9.7 mi
21738 Glenwood, MD 3,268 8.0 mi

More ZIP Codes in Carroll County

21784 standard
Sykesville, MD
Pop: 37,941
21157 standard
Westminster, MD
Pop: 36,920
21158 standard
Westminster, MD
Pop: 20,234
21074 standard
Hampstead, MD
Pop: 15,084
21102 standard
Manchester, MD
Pop: 11,751
21787 standard
Taneytown, MD
Pop: 10,693

Related Areas

Carroll County Marriottsville, MD Maryland

Frequently Asked Questions

What county is ZIP code 21104 in? ▼
ZIP code 21104 (Marriottsville) is located in Carroll County, Maryland. Carroll County contains multiple ZIP codes, see the full list at /counties/carroll-md.
What is the population of ZIP code 21104? ▼
ZIP code 21104 in Marriottsville, MD has a population of 4,601 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 21104? ▼
The median household income in ZIP 21104 is $191,804, which is 151% above the national average of $76,288.
What is the average home value in ZIP 21104? ▼
The median home value in ZIP 21104 is $680,200, which is 145% above the national average of $278,155.
What is the demographic makeup of ZIP 21104? ▼
The largest racial group in ZIP 21104 is White at 75.5%. Hispanic or Latino residents make up 1.0% of the population.
How many businesses are in ZIP code 21104? ▼
ZIP code 21104 has 157 business establishments employing approximately 1,322 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 21104? ▼
The top industries by establishment count in ZIP 21104 are: Professional, scientific, and technical services (40), Construction (20), Health care and social assistance (16). There are 12 industry sectors represented in total.
How have home values changed in ZIP code 21104? ▼
According to the FHFA House Price Index, home values in ZIP 21104 decreased by 3.1% in 2024. Since 2000, home values in this ZIP have appreciated by approximately 152%. This is a developmental index based on repeat sales and appraisal data from Fannie Mae and Freddie Mac.
What is the education level in ZIP code 21104? ▼
In ZIP code 21104, 79.6% of residents aged 25+ have a high school diploma or higher, and 64.4% hold a bachelor's degree or higher. These figures come from the Census Bureau ACS 5-Year Estimates (2023).
What is the average commute time in ZIP 21104? ▼
The mean commute time for workers in ZIP code 21104 is 31.9 minutes according to Census ACS data. The national average is roughly 26 minutes, so commuters here spend more time traveling to work than typical.
What percentage of residents own vs. rent in ZIP 21104? ▼
In ZIP code 21104, approximately 97.0% of occupied housing units are owner-occupied and 3.0% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 21104? ▼
The poverty rate in ZIP code 21104 is 2.7% according to Census Bureau ACS 2023 estimates. This measures the percentage of the population living below the federal poverty threshold.

Read our methodology to see how this data is sourced, computed, and verified.