ZIP Code 66427 — Frankfort, KS
66427 is a standard (street delivery) ZIP code serving Frankfort, Kansas, in Marshall 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 66427 at a glance
| ZIP code | 66427 |
|---|---|
| Primary city | Frankfort |
| State | Kansas (KS) |
| County | Marshall FIPS 20117 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 1,334 |
| Coordinates | 39.662610, -96.449000 |
How ZIP+4 works in 66427
The four digits after the hyphen encode a delivery segment inside 66427. 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 66427 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 66427.
| ZIP | City | Distance |
|---|---|---|
| 66544 | Vermillion, KS | 9.3 mi |
| 66411 | Blue Rapids, KS | 10.2 mi |
| 66438 | Home, KS | 12.1 mi |
| 66406 | Beattie, KS | 16 mi |
| 66549 | Westmoreland, KS | 16.1 mi |
| 66415 | Centralia, KS | 16.3 mi |
| 66548 | Waterville, KS | 16.6 mi |
| 66508 | Marysville, KS | 17 mi |
| 66521 | Onaga, KS | 17.6 mi |
| 66403 | Axtell, KS | 18.6 mi |
| 66520 | Olsburg, KS | 19.6 mi |
| 66404 | Baileyville, KS | 20.2 mi |
Questions about 66427
What is the ZIP+4 code for 66427?
66427 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 66427, you need to look up a specific street address to get them.
What city is 66427?
66427 is assigned to Frankfort, Kansas, in Marshall 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.