ZIP Code 40020 — Fairfield, KY
40020 is a standard (street delivery) ZIP code serving Fairfield, Kentucky, in Nelson 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 40020 at a glance
| ZIP code | 40020 |
|---|---|
| Primary city | Fairfield |
| State | Kentucky (KY) |
| County | Nelson FIPS 21179 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 199 |
| Coordinates | 37.935030, -85.387530 |
How ZIP+4 works in 40020
The four digits after the hyphen encode a delivery segment inside 40020. 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 40020 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 40020.
| ZIP | City | Distance |
|---|---|---|
| 40013 | Coxs Creek, KY | 5.4 mi |
| 40008 | Bloomfield, KY | 5.9 mi |
| 40071 | Taylorsville, KY | 7.5 mi |
| 40004 | Bardstown, KY | 10.2 mi |
| 40047 | Mount Washington, KY | 11.6 mi |
| 40012 | Chaplin, KY | 11.8 mi |
| 40046 | Mount Eden, KY | 13 mi |
| 40110 | Clermont, KY | 13.7 mi |
| 40078 | Willisburg, KY | 14.5 mi |
| 40022 | Finchville, KY | 15.3 mi |
| 40023 | Fisherville, KY | 15.8 mi |
| 40165 | Shepherdsville, KY | 16.9 mi |
Questions about 40020
What is the ZIP+4 code for 40020?
40020 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 40020, you need to look up a specific street address to get them.
What city is 40020?
40020 is assigned to Fairfield, Kentucky, in Nelson 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.