ZIP Code 63544 — Green Castle, MO
63544 is a standard (street delivery) ZIP code serving Green Castle, Missouri, in Adair 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 63544 at a glance
| ZIP code | 63544 |
|---|---|
| Primary city | Green Castle |
| State | Missouri (MO) |
| County | Adair FIPS 29001 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 1,159 |
| Coordinates | 40.246030, -92.849430 |
How ZIP+4 works in 63544
The four digits after the hyphen encode a delivery segment inside 63544. 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 63544 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 63544.
| ZIP | City | Distance |
|---|---|---|
| 63559 | Novinger, MO | 5.6 mi |
| 63545 | Green City, MO | 6.4 mi |
| 63567 | Worthington, MO | 13.8 mi |
| 63501 | Kirksville, MO | 14.7 mi |
| 63556 | Milan, MO | 14.8 mi |
| 63566 | Winigan, MO | 15.7 mi |
| 63560 | Pollock, MO | 16.3 mi |
| 63565 | Unionville, MO | 17.2 mi |
| 63557 | New Boston, MO | 18.2 mi |
| 63551 | Livonia, MO | 18.4 mi |
| 63546 | Greentop, MO | 18.9 mi |
| 63561 | Queen City, MO | 19.9 mi |
Questions about 63544
What is the ZIP+4 code for 63544?
63544 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 63544, you need to look up a specific street address to get them.
What city is 63544?
63544 is assigned to Green Castle, Missouri, in Adair 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.