13 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 03246 | Laconia | 17,006 |
| 03249 | Gilford | 7,785 |
| 03220 | Belmont | 7,376 |
| 03253 | Meredith | 6,677 |
| 03225 | Center Barnstead | 3,770 |
| 03809 | Alton | 3,684 |
| 03269 | Sanbornton | 2,946 |
| 03256 | New Hampton | 2,473 |
| 03237 | Gilmanton | 2,313 |
| 03810 | Alton Bay | 2,269 |
| 03837 | Gilmanton Iron Works | 1,684 |
| 03218 | Barnstead | 1,202 |
| 03226 | Center Harbor | 998 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 13 ZCTAs in Belknap County, New Hampshire (US Census).