ZIP codes

ZIP codes in Howard County, Maryland

Howard County has 25 ZIP codes. 14 lie entirely inside it and 11 are shared with neighboring counties, so part of their land and their people are elsewhere. About 334,175 people live in the parts inside it (ACS 2020–2024).

By the All Map Tools Team

ZIP codes: 25; With 1% or more of their land inside
Entirely inside: 14; 99% or more of their land
Shared with other counties: 11; Most with Carroll County (4)
Most populated ZIP: 21043; 48,525 people · Ellicott City
Least populated ZIP: 20701; 513 people · Jessup
Largest ZIP by land: 21797; 44 sq mi · Lisbon

Map of the ZIP codes in Howard County

Entirely in the county (99% or more of its land)
Shared, mostly in this county
Shared, mostly in other counties
Neighboring counties

Open in the interactive tool

Each area is a ZIP code with its number where it fits. Hover over one to see its name.

All ZIP codes in Howard County

25 ZIP codes in Howard County, MD, by number
ZIP code	Main city	Population	Land in the county	Residents in the county
20701	Jessup	513	54%	≈ 383
20723	North Laurel	36,866	100%	36,866
20759	Fulton	6,624	100%	6,624
20763	Savage	2,601	100%	2,601
20777	Highland	3,221	98%	≈ 3,151
20794	Jessup	16,814	66%	≈ 9,464
20833	Olney	7,860	9.8%	≈ 576
21029	Columbia	13,607	100%	13,607
21036	—	2,569	100%	2,569
21042	Ellicott City	43,327	100%	43,327
21043	Ellicott City	48,525	97%	≈ 47,198
21044	Columbia	44,114	100%	44,114
21045	Columbia	40,034	100%	40,034
21046	Columbia	15,608	100%	15,608
21075	Elkridge	37,363	100%	37,363
21076	Severn	24,268	10%	≈ 3,747
21104	Eldersburg	6,052	53%	≈ 3,513
21163	Randallstown	7,539	27%	≈ 2,490
21723	—	669	100%	669
21737	—	2,474	100%	2,474
21738	—	3,696	100%	3,696
21771	Green Valley	33,031	18%	≈ 3,716
21784	Eldersburg	39,258	18%	≈ 2,921
21794	—	2,192	100%	2,192
21797	Lisbon	8,643	67%	≈ 5,272

ZIP codes shared with other counties

These 11 ZIP codes have part of their land in another county. The first figure is the share of their land in Howard County; then, where the rest lies.

20701 (Jessup): 54% here; 46% in Anne Arundel County.
20777 (Highland): 98% here; 1.7% in Montgomery County.
20794 (Jessup): 66% here; 34% in Anne Arundel County.
20833 (Olney): 9.8% here; 90% in Montgomery County.
21043 (Ellicott City): 97% here; 3.2% in Baltimore County.
21076 (Severn): 10% here; 90% in Anne Arundel County.
21104 (Eldersburg): 53% here; 32% in Carroll County and 15% in Baltimore County.
21163 (Randallstown): 27% here; 73% in Baltimore County.
21771 (Green Valley): 18% here; 51% in Frederick County, 26% in Carroll County, and 4.2% in Montgomery County.
21784 (Eldersburg): 18% here; 82% in Carroll County.
21797 (Lisbon): 67% here; 32% in Carroll County and 1.3% in Montgomery County.

Cities and prefixes

By main city (the city, town or CDP each ZIP shares the most land with), the ones with the most are Columbia (4), Eldersburg (2), Ellicott City (2), Jessup (2), Elkridge (1), and Fulton (1); 14 places in all.

They start with 5 different three-digit prefixes, one per USPS sorting center: 207, 208, 210, 211, and 217.

Neighboring counties

Each one with its ZIP codes. Those without a page of their own open in the tool.

Tools for this county

ZIP codes by county or city The same ZIP codes on an interactive map, with the list as CSV or to copy County map with cities Its cities, towns and CDPs with their population ZIP codes in a radius The ZIP codes within 10 miles of its center, or any distance you like

Sources

U.S. Census Bureau, 2020 ZCTA to County, ZCTA to Place and ZCTA to Census Tract Relationship Files (and the 2022 County Subdivision to ZCTA file for Connecticut). Public domain.
U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates, table B01003 (population of each ZIP code, census tract and Connecticut town). Public domain.
U.S. Census Bureau, Vintage 2025 Population Estimates (county population) and 2025 Gazetteer Files (land area and interior point of each ZIP code). Public domain.
U.S. Census Bureau, Cartographic Boundary Files: ZCTAs 2020 and counties 2025, 1:500,000; county adjacency file 2025. Public domain.

How we count. ZIP codes here are the Census Bureau’s ZIP Code Tabulation Areas (ZCTAs), the areas it draws to match USPS ZIP codes; ZIPs with no area of their own (PO boxes, single buildings) aren’t included. A ZIP can cross county lines: “Land in the county” is the exact share of its land inside, from the Census relationship files. “Residents in the county” is the whole ZIP for those entirely inside; for shared ones it’s an estimate, spreading the people of each census tract over the land it shares with the ZIP. Population: ACS 2020–2024. Methodology.

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