ZIP Code 02558 — Onset, MA
02558 is a standard (street delivery) ZIP code serving Onset, Massachusetts, in Plymouth 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 02558 at a glance
| ZIP code | 02558 |
|---|---|
| Primary city | Onset |
| State | Massachusetts (MA) |
| County | Plymouth FIPS 25023 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 1,734 |
| Coordinates | 41.744530, -70.653770 |
How ZIP+4 works in 02558
The four digits after the hyphen encode a delivery segment inside 02558. 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 02558 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 02558.
| ZIP | City | Distance |
|---|---|---|
| 02538 | East Wareham, MA | 2.4 mi |
| 02571 | Wareham, MA | 2.7 mi |
| 02553 | Monument Beach, MA | 2.8 mi |
| 02532 | Buzzards Bay, MA | 3 mi |
| 02559 | Pocasset, MA | 4.1 mi |
| 02534 | Cataumet, MA | 5.7 mi |
| 02576 | West Wareham, MA | 6.1 mi |
| 02738 | Marion, MA | 6.2 mi |
| 02542 | Buzzards Bay, MA | 6.2 mi |
| 02561 | Sagamore, MA | 6.4 mi |
| 02562 | Sagamore Beach, MA | 7.1 mi |
| 02366 | South Carver, MA | 7.2 mi |
Questions about 02558
What is the ZIP+4 code for 02558?
02558 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 02558, you need to look up a specific street address to get them.
What city is 02558?
02558 is assigned to Onset, Massachusetts, in Plymouth 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.