ZIP Code 01366 — Petersham, MA
01366 is a standard (street delivery) ZIP code serving Petersham, Massachusetts, in Worcester 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 01366 at a glance
| ZIP code | 01366 |
|---|---|
| Primary city | Petersham |
| State | Massachusetts (MA) |
| County | Worcester FIPS 25027 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 1,185 |
| Coordinates | 42.488580, -72.185640 |
How ZIP+4 works in 01366
The four digits after the hyphen encode a delivery segment inside 01366. 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 01366 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 01366.
| ZIP | City | Distance |
|---|---|---|
| 01331 | Athol, MA | 5.5 mi |
| 01005 | Barre, MA | 6.2 mi |
| 01468 | Templeton, MA | 7.4 mi |
| 01355 | New Salem, MA | 7.9 mi |
| 01037 | Hardwick, MA | 8.2 mi |
| 01074 | South Barre, MA | 8.4 mi |
| 01094 | Wheelwright, MA | 8.9 mi |
| 01438 | East Templeton, MA | 9.1 mi |
| 01452 | Hubbardston, MA | 9.2 mi |
| 01436 | Baldwinville, MA | 9.4 mi |
| 01364 | Orange, MA | 9.7 mi |
| 01031 | Gilbertville, MA | 11.1 mi |
Questions about 01366
What is the ZIP+4 code for 01366?
01366 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 01366, you need to look up a specific street address to get them.
What city is 01366?
01366 is assigned to Petersham, Massachusetts, in Worcester 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.