ZIP Code 11901 — Riverhead, NY
11901 is a standard (street delivery) ZIP code serving Riverhead, New York, in Suffolk 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 11901 at a glance
| ZIP code | 11901 |
|---|---|
| Primary city | Riverhead |
| State | New York (NY) |
| County | Suffolk FIPS 36103 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 33,091 |
| Coordinates | 40.924240, -72.646970 |
How ZIP+4 works in 11901
The four digits after the hyphen encode a delivery segment inside 11901. 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 11901 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 11901.
| ZIP | City | Distance |
|---|---|---|
| 11931 | Aquebogue, NY | 1.5 mi |
| 11947 | Jamesport, NY | 3.6 mi |
| 11970 | South Jamesport, NY | 4 mi |
| 11948 | Laurel, NY | 5.5 mi |
| 11933 | Calverton, NY | 5.6 mi |
| 11942 | East Quogue, NY | 6.3 mi |
| 11978 | Westhampton Beach, NY | 6.6 mi |
| 11959 | Quogue, NY | 6.8 mi |
| 11977 | Westhampton, NY | 6.9 mi |
| 11941 | Eastport, NY | 7.4 mi |
| 11952 | Mattituck, NY | 7.4 mi |
| 11972 | Speonk, NY | 7.5 mi |
Questions about 11901
What is the ZIP+4 code for 11901?
11901 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 11901, you need to look up a specific street address to get them.
What city is 11901?
11901 is assigned to Riverhead, New York, in Suffolk 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.