ZIP Code 51431 — Arthur, IA
51431 is a standard (street delivery) ZIP code serving Arthur, Iowa, in Ida 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 51431 at a glance
| ZIP code | 51431 |
|---|---|
| Primary city | Arthur |
| State | Iowa (IA) |
| County | Ida FIPS 19093 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 430 |
| Coordinates | 42.344460, -95.351460 |
How ZIP+4 works in 51431
The four digits after the hyphen encode a delivery segment inside 51431. 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 51431 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 51431.
| ZIP | City | Distance |
|---|---|---|
| 51445 | Ida Grove, IA | 6 mi |
| 51458 | Odebolt, IA | 6.1 mi |
| 51448 | Kiron, IA | 10 mi |
| 51053 | Schaller, IA | 10.8 mi |
| 51020 | Galva, IA | 12 mi |
| 50535 | Early, IA | 12.2 mi |
| 51006 | Battle Creek, IA | 13.5 mi |
| 51461 | Schleswig, IA | 13.5 mi |
| 51466 | Wall Lake, IA | 14.4 mi |
| 51025 | Holstein, IA | 14.9 mi |
| 51441 | Deloit, IA | 15.7 mi |
| 51450 | Lake View, IA | 16.7 mi |
Questions about 51431
What is the ZIP+4 code for 51431?
51431 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 51431, you need to look up a specific street address to get them.
What city is 51431?
51431 is assigned to Arthur, Iowa, in Ida 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.