ZIP Code 40456 — Mount Vernon, KY
40456 is a standard (street delivery) ZIP code serving Mount Vernon, Kentucky, in Rockcastle 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 40456 at a glance
| ZIP code | 40456 |
|---|---|
| Primary city | Mount Vernon |
| State | Kentucky (KY) |
| County | Rockcastle FIPS 21203 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 8,370 |
| Coordinates | 37.353800, -84.320990 |
How ZIP+4 works in 40456
The four digits after the hyphen encode a delivery segment inside 40456. 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 40456 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 40456.
| ZIP | City | Distance |
|---|---|---|
| 40460 | Orlando, KY | 5.2 mi |
| 40409 | Brodhead, KY | 6.2 mi |
| 40445 | Livingston, KY | 6.6 mi |
| 40419 | Crab Orchard, KY | 11.4 mi |
| 40729 | East Bernstadt, KY | 12.2 mi |
| 40481 | Sandgap, KY | 13.6 mi |
| 40404 | Berea, KY | 15.2 mi |
| 40403 | Berea, KY | 15.3 mi |
| 42567 | Eubank, KY | 16.7 mi |
| 40461 | Paint Lick, KY | 17 mi |
| 40447 | Mckee, KY | 17.4 mi |
| 42503 | Somerset, KY | 17.6 mi |
Questions about 40456
What is the ZIP+4 code for 40456?
40456 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 40456, you need to look up a specific street address to get them.
What city is 40456?
40456 is assigned to Mount Vernon, Kentucky, in Rockcastle 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.