ZIP Code 17857 — Northumberland, PA
17857 is a standard (street delivery) ZIP code serving Northumberland, Pennsylvania, in Northumberland 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 17857 at a glance
| ZIP code | 17857 |
|---|---|
| Primary city | Northumberland |
| State | Pennsylvania (PA) |
| County | Northumberland FIPS 42097 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 7,671 |
| Coordinates | 40.927890, -76.767120 |
How ZIP+4 works in 17857
The four digits after the hyphen encode a delivery segment inside 17857. 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 17857 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 17857.
| ZIP | City | Distance |
|---|---|---|
| 17865 | Potts Grove, PA | 4.2 mi |
| 17850 | Montandon, PA | 5.5 mi |
| 17876 | Shamokin Dam, PA | 5.8 mi |
| 17847 | Milton, PA | 5.8 mi |
| 17801 | Sunbury, PA | 6.3 mi |
| 17868 | Riverside, PA | 7.3 mi |
| 17821 | Danville, PA | 8 mi |
| 17889 | Winfield, PA | 8.3 mi |
| 17886 | West Milton, PA | 8.4 mi |
| 17822 | Danville, PA | 9 mi |
| 17837 | Lewisburg, PA | 9.7 mi |
| 17860 | Paxinos, PA | 9.8 mi |
Questions about 17857
What is the ZIP+4 code for 17857?
17857 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 17857, you need to look up a specific street address to get them.
What city is 17857?
17857 is assigned to Northumberland, Pennsylvania, in Northumberland 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.