ZIP Code 03237 — Gilmanton, NH
03237 is a standard (street delivery) ZIP code serving Gilmanton, New Hampshire, in Belknap County. To mail something here you only need these five digits — but the four-digit extension narrows delivery to a single point, and it is what USPS bulk postage discounts are priced on.
ZIP code 03237 at a glance
| ZIP code | 03237 |
|---|---|
| Primary city | Gilmanton |
| State | New Hampshire (NH) |
| County | Belknap FIPS 33001 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 2,575 |
| Coordinates | 43.429970, -71.382330 |
How ZIP+4 works in 03237
The four digits after the hyphen encode a delivery segment inside 03237. In practice one segment usually means:
- One side of one block — odd numbers on a street between two cross streets
- A single large building, or one floor of it
- A group of PO boxes, sometimes a single box
- A single business that receives enough mail to warrant its own code
That is why 03237 has no single ZIP+4: two neighbors across the street from each other usually have different ones. Enter a street address above and we will return the exact nine-digit code along with the standardized USPS address format.
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 03237.
| ZIP | City | Distance |
|---|---|---|
| 03837 | Gilmanton Iron Works, NH | 2.8 mi |
| 03220 | Belmont, NH | 5.4 mi |
| 03307 | Loudon, NH | 8 mi |
| 03218 | Barnstead, NH | 8.1 mi |
| 03810 | Alton Bay, NH | 8.4 mi |
| 03225 | Center Barnstead, NH | 8.7 mi |
| 03809 | Alton, NH | 8.7 mi |
| 03249 | Gilford, NH | 8.8 mi |
| 03276 | Tilton, NH | 9.7 mi |
| 03224 | Canterbury, NH | 9.9 mi |
| 03263 | Pittsfield, NH | 10 mi |
| 03246 | Laconia, NH | 10.9 mi |
Questions about 03237
What is the ZIP+4 code for 03237?
03237 is the five-digit ZIP code. The ZIP+4 adds four more digits that identify a specific delivery point — usually one side of a city block, a single building, or a group of PO boxes. Because those four digits change from address to address within 03237, you need to look up a specific street address to get them.
What city is 03237?
03237 is assigned to Gilmanton, New Hampshire, in Belknap County.
Do I need to use the ZIP+4?
It is optional for ordinary mail, but it speeds up sorting and it is required for most USPS bulk-mail postage discounts. Many address-verification and e-commerce systems also use ZIP+4 to confirm a delivery point exists.
Need thousands of these?
Upload a CSV and get ZIP+4, county, carrier route, and delivery-point data appended to every row — or call the API directly.