ZIP Code 18921 — Ferndale, PA
18921 is a standard (street delivery) ZIP code serving Ferndale, Pennsylvania, in Bucks 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 18921 at a glance
| ZIP code | 18921 |
|---|---|
| Primary city | Ferndale |
| State | Pennsylvania (PA) |
| County | Bucks FIPS 42017 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 160 |
| Coordinates | 40.529460, -75.173800 |
How ZIP+4 works in 18921
The four digits after the hyphen encode a delivery segment inside 18921. 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 18921 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 18921.
| ZIP | City | Distance |
|---|---|---|
| 18930 | Kintnersville, PA | 2.1 mi |
| 18972 | Upper Black Eddy, PA | 2.8 mi |
| 18942 | Ottsville, PA | 4 mi |
| 18077 | Riegelsville, PA | 4.3 mi |
| 18920 | Erwinna, PA | 5 mi |
| 08848 | Milford, NJ | 6 mi |
| 18081 | Springtown, PA | 6.2 mi |
| 18055 | Hellertown, PA | 7.7 mi |
| 18947 | Pipersville, PA | 7.8 mi |
| 18955 | Richlandtown, PA | 8 mi |
| 08825 | Frenchtown, NJ | 8 mi |
| 18950 | Point Pleasant, PA | 8 mi |
Questions about 18921
What is the ZIP+4 code for 18921?
18921 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 18921, you need to look up a specific street address to get them.
What city is 18921?
18921 is assigned to Ferndale, Pennsylvania, in Bucks 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.