Home > MD > Howard County > Marriottsville > Zip 21104

Zip Code 21104 — Marriottsville, MD

ZIP Code 21104 is associated with Marriottsville, MD, in Howard County. The listed population estimate is 6,052; estimated density is 137.0 people per square mile. Among records with population estimates, it ranks #12 of 20 in Howard County and #224 of 470 in MD.
Page generated: 2026-10-08. This is not the source data release date.

📍 View location on OpenStreetMap (39.350440, -76.906540)

Data MetricLocal Statistic
Postal / Zip Code21104
Primary CityMarriottsville
State / ProvinceMD
CountyHoward
Total Population6,052
Population Density137.0 people/sq mi
TimezoneAmerica/New_York

How 21104 Compares

MetricZIP 21104Howard County recordsMD records
Population estimate6,052335,512 (sum)6,205,597 (sum)
Population Density137.0 /sq mi----
County population rank#12 of 20----
State population rank#224 of 470----

Regional sums combine the population estimates in the listed ZIP records; they are not official county or state population totals.

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Nearby ZIP Codes in MD

ZIP CodeCityDistancePopulation estimate
ZIP 21163Woodstock2.7 mi7,539
ZIP 21784Sykesville5.0 mi39,258
ZIP 21794West Friendship5.2 mi2,192
ZIP 21133Randallstown5.4 mi31,398
ZIP 21042Ellicott City5.5 mi43,327

Data Sources & Methodology: Geographic coordinates and ZIP Code assignments are derived from underlying geographic and postal datasets. Note that ZIP Codes are USPS postal delivery areas, while Census ZCTAs are statistical approximation areas. Read full methodology →