ZIP Code 63648 — Irondale, MO
63648 is a standard (street delivery) ZIP code serving Irondale, Missouri, in Washington 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 63648 at a glance
| ZIP code | 63648 |
|---|---|
| Primary city | Irondale |
| State | Missouri (MO) |
| County | Washington FIPS 29221 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 1,858 |
| Coordinates | 37.818700, -90.698780 |
How ZIP+4 works in 63648
The four digits after the hyphen encode a delivery segment inside 63648. 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 63648 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 63648.
| ZIP | City | Distance |
|---|---|---|
| 63624 | Bismarck, MO | 5.6 mi |
| 63660 | Mineral Point, MO | 6.5 mi |
| 63653 | Leadwood, MO | 6.7 mi |
| 63631 | Caledonia, MO | 6.9 mi |
| 63601 | Park Hills, MO | 8.4 mi |
| 63622 | Belgrade, MO | 11.5 mi |
| 63637 | Doe Run, MO | 12.6 mi |
| 63628 | Bonne Terre, MO | 12.6 mi |
| 63663 | Pilot Knob, MO | 13.7 mi |
| 63664 | Potosi, MO | 13.8 mi |
| 63630 | Cadet, MO | 13.9 mi |
| 63623 | Belleview, MO | 14.5 mi |
Questions about 63648
What is the ZIP+4 code for 63648?
63648 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 63648, you need to look up a specific street address to get them.
What city is 63648?
63648 is assigned to Irondale, Missouri, in Washington 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.