48 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 20906 | Silver Spring | 71,216 |
| 20878 | Gaithersburg | 65,236 |
| 20874 | Germantown | 62,233 |
| 20904 | Silver Spring | 57,244 |
| 20902 | Silver Spring | 53,170 |
| 20850 | Rockville | 50,365 |
| 20854 | Potomac | 49,694 |
| 20852 | Rockville | 47,857 |
| 20910 | Silver Spring | 45,096 |
| 20877 | Gaithersburg | 39,068 |
| 20817 | Bethesda | 37,738 |
| 20901 | Silver Spring | 37,338 |
| 20886 | Montgomery Village | 34,419 |
| 20853 | Rockville | 31,438 |
| 20815 | Chevy Chase | 31,269 |
| 20814 | Bethesda | 30,822 |
| 20871 | Clarksburg | 28,329 |
| 20876 | Germantown | 26,511 |
| 20879 | Gaithersburg | 26,120 |
| 20832 | Olney | 25,766 |
| 20903 | Silver Spring | 25,540 |
| 20912 | Takoma Park | 25,428 |
| 20895 | Kensington | 19,042 |
| 20905 | Silver Spring | 18,268 |
| 20816 | Bethesda | 18,081 |
| 20855 | Derwood | 16,557 |
| 20866 | Burtonsville | 16,499 |
| 20851 | Rockville | 14,660 |
| 20882 | Gaithersburg | 13,661 |
| 20872 | Damascus | 13,138 |
| 20841 | Boyds | 9,706 |
| 20833 | Brookeville | 7,868 |
| 20837 | Poolesville | 6,605 |
| 20861 | Ashton | 3,020 |
| 20842 | Dickerson | 2,093 |
| 20860 | Sandy Spring | 2,062 |
| 20818 | Cabin John | 1,602 |
| 20896 | Garrett Park | 890 |
| 20880 | Washington Grove | 590 |
| 20838 | Barnesville | 409 |
| 20862 | Brinklow | 393 |
| 20868 | Spencerville | 384 |
| 20812 | Glen Echo | 314 |
| 20889 | Bethesda | 210 |
| 20839 | Beallsville | 116 |
| 20899 | Gaithersburg | 106 |
| 20894 | Bethesda | 0 |
| 20892 | Bethesda | 0 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 48 ZCTAs in Montgomery County, Maryland (US Census).