ZIP Code 01003 — Amherst, MA
01003 is a standard (street delivery) ZIP code serving Amherst, Massachusetts, in Hampshire 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 01003 at a glance
| ZIP code | 01003 |
|---|---|
| Primary city | Amherst |
| State | Massachusetts (MA) |
| County | Hampshire FIPS 25015 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 13,510 |
| Coordinates | 42.391350, -72.523270 |
How ZIP+4 works in 01003
The four digits after the hyphen encode a delivery segment inside 01003. 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 01003 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.
Other ZIP codes in Amherst
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 01003.
| ZIP | City | Distance |
|---|---|---|
| 01002 | Amherst, MA | 3.2 mi |
| 01035 | Hadley, MA | 3.4 mi |
| 01038 | Hatfield, MA | 4.2 mi |
| 01375 | Sunderland, MA | 5.3 mi |
| 01054 | Leverett, MA | 6 mi |
| 01066 | North Hatfield, MA | 6.1 mi |
| 01088 | West Hatfield, MA | 6.3 mi |
| 01060 | Northampton, MA | 7.3 mi |
| 01072 | Shutesbury, MA | 7.3 mi |
| 01373 | South Deerfield, MA | 7.3 mi |
| 01093 | Whately, MA | 7.4 mi |
| 01063 | Northampton, MA | 7.7 mi |
Questions about 01003
What is the ZIP+4 code for 01003?
01003 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 01003, you need to look up a specific street address to get them.
What city is 01003?
01003 is assigned to Amherst, Massachusetts, in Hampshire 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.