County ZIP codes · Maryland · FIPS 24027
Howard County, MD ZIP Codes
Howard County, Maryland has 29 ZIP codes (Census 2020 ZCTA-county file; GeoNames postal codes, October 2026): 25 residential and 4 for PO boxes or a single organization. 20 of the residential ones lie mainly in Howard County and 5 mainly in a neighboring county; 11 cross the county line. Median household income ranges from $116,406 in 20794 (Jessup) to $250,000 or more in 3 ZIP codes at the Census top code (Census Bureau, ACS 2020-2024).
- ACS2020-24
- Census2020
Where are the ZIP codes of Howard County?
Source: U.S. Census Bureau, 2020 ZCTA cartographic boundaries; ACS 2020-2024 5-year estimates (B19013).
How different are its ZIP codes?
The middle half of its ranked ZIP codes (1,000+ people living in households) report median household incomes between $135,057 and $190,061. 3 report $250,000 or more, the Census top code.
They carry 22 postal town names.
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates (B19013).
All 25 residential ZIP codes in Howard County
20 ZIP codes lie mainly in Howard County; 5 more reach into it from a neighboring county and follow the first table.
| In this county | ||||||
|---|---|---|---|---|---|---|
| 21043 | Ellicott City | 48,525 | 2,838 | $148k | $621k | 97% |
| 21044 | Columbia | 44,114 | 3,711 | $135k | $567k | 100% |
| 21042 | Ellicott City | 43,327 | 1,171 | $190k | $706k | 100% |
| 21045 | Columbia | 40,034 | 4,128 | $119k | $454k | 100% |
| 21075 | Elkridge | 37,363 | 2,682 | $135k | $455k | 100% |
| 20723 | Laurel | 36,866 | 2,832 | $138k | $525k | 100% |
| 20794 | Jessup | 16,814 | 1,743 | $116k | $426k | 66% |
| 21046 | Columbia | 15,608 | 1,998 | $128k | $480k | 100% |
| 21029 | Clarksville | 13,607 | 804 | $244k | $912k | 100% |
| 21797 | Woodbine | 8,643 | 198 | $189k | $736k | 67% |
| 20759 | Fulton | 6,624 | 1,054 | $250k+ | $955k | 100% |
| 21104 | Marriottsville | 6,052 | 355 | $192k | $680k | 53% |
| 21738 | Glenwood | 3,696 | 530 | $250k+ | $914k | 100% |
| 20777 | Highland | 3,221 | 427 | $226k | $862k | 98% |
| 20763 | Savage | 2,601 | 2,440 | $77k | $419k | 100% |
| 21036 | Dayton | 2,569 | 411 | $218k | $881k | 100% |
| 21737 | Glenelg | 2,474 | 483 | $250k+ | $996k | 100% |
| 21794 | West Friendship | 2,192 | 269 | $232k | $999k | 100% |
| 21723 | Cooksville | 669 | 186 | $241k | $1.01M | 100% |
| 20701 | Annapolis Junction | 513 | 233 | $86k | – | 54% |
Partly in Howard County
| In this county | ||||||
|---|---|---|---|---|---|---|
| 21163 | Woodstock | 7,539 | 553 | $135k | $603k | 27% |
| 21771 | Mount Airy | 33,031 | 369 | $157k | $556k | 18% |
| 21784 | Sykesville | 39,258 | 699 | $139k | $492k | 18% |
| 21076 | Hanover | 24,268 | 1,846 | $147k | $513k | 10% |
| 20833 | Brookeville | 7,860 | 411 | $204k | $797k | 10% |
Source: U.S. Census Bureau, ACS 2020-2024 5-year estimates; county shares by land area (Census 2020 ZCTA-county relationship file).
Which ZIP codes cross the county line?
11 ZIP codes of Howard County extend into another county. A ZIP code follows mail routes, not county borders.
| ZIP | In Howard | Elsewhere |
|---|---|---|
| 21043 | 97% | Baltimore County3% |
| 21784 | 18% | Carroll County82% |
| 21771 | 18% | Frederick County51%; Carroll County26%; Montgomery County4% |
| 21076 | 10% | Anne Arundel County90% |
| 20794 | 66% | Anne Arundel County34% |
| 21797 | 67% | Carroll County32%; Montgomery County1% |
| 20833 | 10% | Montgomery County90% |
| 21163 | 27% | Baltimore County73% |
| 21104 | 53% | Carroll County32%; Baltimore County15% |
| 20777 | 98% | Montgomery County2% |
| 20701 | 54% | Anne Arundel County46% |
Source: U.S. Census Bureau, 2020 ZCTA-county relationship file (shares of land area).
PO Box and single-organization ZIP codes
| ZIP | Postal name |
|---|---|
| 20588 | Dhs |
| 21041 | Ellicott City |
| 21150 | Simpsonville |
| 21765 | Lisbon |
Source: GeoNames postal codes (CC BY 4.0).
Which first three digits do Howard County's ZIP codes use?
The first three digits of a ZIP code name the sectional center, the mail processing plant that sorts it. Howard County's ZIP codes use 6 prefixes: 205, 207, 208, 210, 211 and 217.
| Prefix | Sectional center | Here | All codes |
|---|---|---|---|
| 205 | Washington, DC (SCF 202) | 1 | 72 |
| 207 | Southern, MD (SCF 207) | 6 | 79 |
| 208 | Suburban, MD (SCF 208) | 1 | 59 |
| 210 | Linthicum, MD (SCF 210) | 10 | 58 |
| 211 | Linthicum, MD (SCF 210) | 3 | 34 |
| 217 | Baltimore, MD (SCF 212) | 8 | 66 |
Source: U.S. Postal Service, labeling list L005 (3-digit ZIP Code prefix groups, SCF sortation), effective October 1, 2026.