20 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 21043 | Ellicott City | 47,309 |
| 21044 | Columbia | 45,100 |
| 21042 | Ellicott City | 42,528 |
| 21045 | Columbia | 40,980 |
| 21075 | Elkridge | 36,176 |
| 20723 | Laurel | 35,845 |
| 20794 | Jessup | 16,035 |
| 21046 | Columbia | 15,894 |
| 21029 | Clarksville | 13,817 |
| 21797 | Woodbine | 9,034 |
| 20759 | Fulton | 6,125 |
| 21104 | Marriottsville | 6,077 |
| 21738 | Glenwood | 3,786 |
| 20777 | Highland | 3,220 |
| 21737 | Glenelg | 2,406 |
| 21794 | West Friendship | 2,309 |
| 20763 | Savage | 2,219 |
| 21036 | Dayton | 2,145 |
| 20701 | Annapolis Junction | 794 |
| 21723 | Cooksville | 689 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 20 ZCTAs in Howard County, Maryland (US Census).