ZIP Code 66066 — Oskaloosa, KS
66066 is a standard (street delivery) ZIP code serving Oskaloosa, Kansas, in Jefferson 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 66066 at a glance
| ZIP code | 66066 |
|---|---|
| Primary city | Oskaloosa |
| State | Kansas (KS) |
| County | Jefferson FIPS 20087 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 2,432 |
| Coordinates | 39.203590, -95.331420 |
How ZIP+4 works in 66066
The four digits after the hyphen encode a delivery segment inside 66066. 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 66066 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 66066.
| ZIP | City | Distance |
|---|---|---|
| 66070 | Ozawkie, KS | 6.4 mi |
| 66054 | Mclouth, KS | 7.3 mi |
| 66073 | Perry, KS | 8.1 mi |
| 66097 | Winchester, KS | 10 mi |
| 66512 | Meriden, KS | 11.5 mi |
| 66088 | Valley Falls, KS | 11.6 mi |
| 66429 | Grantville, KS | 13.2 mi |
| 66044 | Lawrence, KS | 13.5 mi |
| 66050 | Lecompton, KS | 13.9 mi |
| 66086 | Tonganoxie, KS | 14.7 mi |
| 66060 | Nortonville, KS | 14.8 mi |
| 66020 | Easton, KS | 15.3 mi |
Questions about 66066
What is the ZIP+4 code for 66066?
66066 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 66066, you need to look up a specific street address to get them.
What city is 66066?
66066 is assigned to Oskaloosa, Kansas, in Jefferson 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.