ZIP Code 11556 — Uniondale, NY
11556 is a standard (street delivery) ZIP code serving Uniondale, New York, in Nassau 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 11556 at a glance
| ZIP code | 11556 |
|---|---|
| Primary city | Uniondale |
| State | New York (NY) |
| County | Nassau FIPS 36059 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Coordinates | 40.719970, -73.583270 |
How ZIP+4 works in 11556
The four digits after the hyphen encode a delivery segment inside 11556. 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 11556 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.
Other ZIP codes in Uniondale
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 11556.
| ZIP | City | Distance |
|---|---|---|
| 11549 | Hempstead, NY | 0.9 mi |
| 11553 | Uniondale, NY | 1.1 mi |
| 11554 | East Meadow, NY | 1.2 mi |
| 11550 | Hempstead, NY | 2.3 mi |
| 11590 | Westbury, NY | 2.5 mi |
| 11514 | Carle Place, NY | 2.6 mi |
| 11575 | Roosevelt, NY | 2.7 mi |
| 11530 | Garden City, NY | 2.8 mi |
| 11501 | Mineola, NY | 3.4 mi |
| 11756 | Levittown, NY | 3.5 mi |
| 11552 | West Hempstead, NY | 4 mi |
| 11596 | Williston Park, NY | 4.1 mi |
Questions about 11556
What is the ZIP+4 code for 11556?
11556 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 11556, you need to look up a specific street address to get them.
What city is 11556?
11556 is assigned to Uniondale, New York, in Nassau 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.