ZIP Code 37657 — Flag Pond, TN
37657 is a standard (street delivery) ZIP code serving Flag Pond, Tennessee, in Unicoi 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 37657 at a glance
| ZIP code | 37657 |
|---|---|
| Primary city | Flag Pond |
| State | Tennessee (TN) |
| County | Unicoi FIPS 47171 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 1,060 |
| Coordinates | 36.017250, -82.560570 |
How ZIP+4 works in 37657
The four digits after the hyphen encode a delivery segment inside 37657. 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 37657 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 37657.
| ZIP | City | Distance |
|---|---|---|
| 37650 | Erwin, TN | 8.2 mi |
| 28754 | Mars Hill, NC | 10 mi |
| 28753 | Marshall, NC | 12.7 mi |
| 37641 | Chuckey, TN | 13.9 mi |
| 28740 | Green Mountain, NC | 14.5 mi |
| 37690 | Telford, TN | 16.1 mi |
| 37681 | Limestone, TN | 16.8 mi |
| 37743 | Greeneville, TN | 16.9 mi |
| 28714 | Burnsville, NC | 17.1 mi |
| 37616 | Afton, TN | 17.9 mi |
| 37692 | Unicoi, TN | 18.4 mi |
| 37659 | Jonesborough, TN | 18.6 mi |
Questions about 37657
What is the ZIP+4 code for 37657?
37657 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 37657, you need to look up a specific street address to get them.
What city is 37657?
37657 is assigned to Flag Pond, Tennessee, in Unicoi 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.