ZIP Code 51555 — Missouri Valley, IA
51555 is a standard (street delivery) ZIP code serving Missouri Valley, Iowa, in Harrison 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 51555 at a glance
| ZIP code | 51555 |
|---|---|
| Primary city | Missouri Valley |
| State | Iowa (IA) |
| County | Harrison FIPS 19085 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 4,952 |
| Coordinates | 41.559370, -95.913980 |
How ZIP+4 works in 51555
The four digits after the hyphen encode a delivery segment inside 51555. 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 51555 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 51555.
| ZIP | City | Distance |
|---|---|---|
| 51556 | Modale, IA | 8.4 mi |
| 68023 | Fort Calhoun, NE | 8.7 mi |
| 51546 | Logan, IA | 9.2 mi |
| 51550 | Magnolia, IA | 9.4 mi |
| 51542 | Honey Creek, IA | 9.5 mi |
| 68112 | Omaha, NE | 12.5 mi |
| 51557 | Mondamin, IA | 12.6 mi |
| 51526 | Crescent, IA | 13.1 mi |
| 68008 | Blair, NE | 13.5 mi |
| 68152 | Omaha, NE | 14.3 mi |
| 51559 | Neola, IA | 14.8 mi |
| 68122 | Omaha, NE | 15.2 mi |
Questions about 51555
What is the ZIP+4 code for 51555?
51555 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 51555, you need to look up a specific street address to get them.
What city is 51555?
51555 is assigned to Missouri Valley, Iowa, in Harrison 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.