ZIP Code 03031 — Amherst, NH
03031 is a standard (street delivery) ZIP code serving Amherst, New Hampshire, in Hillsborough 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 03031 at a glance
| ZIP code | 03031 |
|---|---|
| Primary city | Amherst |
| State | New Hampshire (NH) |
| County | Hillsborough FIPS 33011 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 11,849 |
| Coordinates | 42.870560, -71.606830 |
How ZIP+4 works in 03031
The four digits after the hyphen encode a delivery segment inside 03031. 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 03031 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 03031.
| ZIP | City | Distance |
|---|---|---|
| 03057 | Mont Vernon, NH | 4.6 mi |
| 03054 | Merrimack, NH | 4.6 mi |
| 03055 | Milford, NH | 5 mi |
| 03110 | Bedford, NH | 6.2 mi |
| 03063 | Nashua, NH | 7.7 mi |
| 03052 | Litchfield, NH | 7.9 mi |
| 03070 | New Boston, NH | 8.4 mi |
| 03049 | Hollis, NH | 8.4 mi |
| 03082 | Lyndeborough, NH | 8.8 mi |
| 03086 | Wilton, NH | 8.8 mi |
| 03033 | Brookline, NH | 9.2 mi |
| 03064 | Nashua, NH | 9.2 mi |
Questions about 03031
What is the ZIP+4 code for 03031?
03031 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 03031, you need to look up a specific street address to get them.
What city is 03031?
03031 is assigned to Amherst, New Hampshire, in Hillsborough 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.