20 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 21043 | Ellicott City | 47,134 |
| 21044 | Columbia | 44,775 |
| 21042 | Ellicott City | 43,021 |
| 21045 | Columbia | 40,866 |
| 21075 | Elkridge | 37,146 |
| 20723 | Laurel | 36,319 |
| 20794 | Jessup | 16,182 |
| 21046 | Columbia | 15,433 |
| 21029 | Clarksville | 13,783 |
| 21797 | Woodbine | 8,772 |
| 20759 | Fulton | 6,758 |
| 21104 | Marriottsville | 5,786 |
| 21738 | Glenwood | 3,668 |
| 20777 | Highland | 3,046 |
| 21737 | Glenelg | 2,384 |
| 21794 | West Friendship | 2,326 |
| 20763 | Savage | 2,320 |
| 21036 | Dayton | 2,162 |
| 20701 | Annapolis Junction | 749 |
| 21723 | Cooksville | 587 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 20 ZCTAs in Howard County, Maryland (US Census).