ZIP Code 03809 — Alton, NH
03809 is a standard (street delivery) ZIP code serving Alton, 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 03809 at a glance
| ZIP code | 03809 |
|---|---|
| Primary city | Alton |
| State | New Hampshire (NH) |
| County | Belknap FIPS 33001 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 3,680 |
| Coordinates | 43.453210, -71.211840 |
How ZIP+4 works in 03809
The four digits after the hyphen encode a delivery segment inside 03809. 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 03809 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 03809.
| ZIP | City | Distance |
|---|---|---|
| 03855 | New Durham, NH | 3.6 mi |
| 03810 | Alton Bay, NH | 6.1 mi |
| 03837 | Gilmanton Iron Works, NH | 6.2 mi |
| 03225 | Center Barnstead, NH | 6.6 mi |
| 03887 | Union, NH | 7.6 mi |
| 03237 | Gilmanton, NH | 8.7 mi |
| 03218 | Barnstead, NH | 9 mi |
| 03835 | Farmington, NH | 9.2 mi |
| 03851 | Milton, NH | 9.9 mi |
| 03894 | Wolfeboro, NH | 11 mi |
| 03249 | Gilford, NH | 11.3 mi |
| 03872 | Sanbornville, NH | 11.8 mi |
Questions about 03809
What is the ZIP+4 code for 03809?
03809 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 03809, you need to look up a specific street address to get them.
What city is 03809?
03809 is assigned to Alton, 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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