ZIP Code 12421 — Denver, NY
12421 is a standard (street delivery) ZIP code serving Denver, New York, in Delaware 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 12421 at a glance
| ZIP code | 12421 |
|---|---|
| Primary city | Denver |
| State | New York (NY) |
| County | Delaware FIPS 36025 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 261 |
| Coordinates | 42.251200, -74.533600 |
How ZIP+4 works in 12421
The four digits after the hyphen encode a delivery segment inside 12421. 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 12421 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 12421.
| ZIP | City | Distance |
|---|---|---|
| 12430 | Fleischmanns, NY | 3.8 mi |
| 12474 | Roxbury, NY | 3.8 mi |
| 12438 | Halcottsville, NY | 4.2 mi |
| 12468 | Prattsville, NY | 7 mi |
| 12441 | Highmount, NY | 7.1 mi |
| 12459 | New Kingston, NY | 7.5 mi |
| 12465 | Pine Hill, NY | 7.6 mi |
| 12434 | Grand Gorge, NY | 8 mi |
| 13788 | Hobart, NY | 9.2 mi |
| 12452 | Lexington, NY | 9.4 mi |
| 12455 | Margaretville, NY | 9.7 mi |
| 12407 | Ashland, NY | 9.8 mi |
Questions about 12421
What is the ZIP+4 code for 12421?
12421 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 12421, you need to look up a specific street address to get them.
What city is 12421?
12421 is assigned to Denver, New York, in Delaware 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.