ZIP Code 03810 — Alton Bay, NH
03810 is a standard (street delivery) ZIP code serving Alton Bay, 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 03810 at a glance
| ZIP code | 03810 |
|---|---|
| Primary city | Alton Bay |
| State | New Hampshire (NH) |
| County | Belknap FIPS 33001 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 2,314 |
| Coordinates | 43.526920, -71.279410 |
How ZIP+4 works in 03810
The four digits after the hyphen encode a delivery segment inside 03810. 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 03810 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 03810.
| ZIP | City | Distance |
|---|---|---|
| 03249 | Gilford, NH | 5.7 mi |
| 03809 | Alton, NH | 6.1 mi |
| 03837 | Gilmanton Iron Works, NH | 7.6 mi |
| 03853 | Mirror Lake, NH | 7.7 mi |
| 03894 | Wolfeboro, NH | 7.7 mi |
| 03855 | New Durham, NH | 8.2 mi |
| 03237 | Gilmanton, NH | 8.4 mi |
| 03246 | Laconia, NH | 10.4 mi |
| 03220 | Belmont, NH | 10.6 mi |
| 03887 | Union, NH | 11.1 mi |
| 03225 | Center Barnstead, NH | 11.7 mi |
| 03850 | Melvin Village, NH | 11.8 mi |
Questions about 03810
What is the ZIP+4 code for 03810?
03810 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 03810, you need to look up a specific street address to get them.
What city is 03810?
03810 is assigned to Alton Bay, 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?
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