ZIP Code 51038 — Merrill, IA
51038 is a standard (street delivery) ZIP code serving Merrill, Iowa, in Plymouth 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 51038 at a glance
| ZIP code | 51038 |
|---|---|
| Primary city | Merrill |
| State | Iowa (IA) |
| County | Plymouth FIPS 19149 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 1,449 |
| Coordinates | 42.705600, -96.315690 |
How ZIP+4 works in 51038
The four digits after the hyphen encode a delivery segment inside 51038. 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 51038 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 51038.
| ZIP | City | Distance |
|---|---|---|
| 51024 | Hinton, IA | 6.4 mi |
| 51008 | Brunsville, IA | 7.7 mi |
| 51031 | Le Mars, IA | 9.6 mi |
| 51108 | Sioux City, IA | 9.8 mi |
| 51062 | Westfield, IA | 11.1 mi |
| 51109 | Sioux City, IA | 11.1 mi |
| 51104 | Sioux City, IA | 12.6 mi |
| 51105 | Sioux City, IA | 13.9 mi |
| 51103 | Sioux City, IA | 14.3 mi |
| 51001 | Akron, IA | 14.8 mi |
| 51101 | Sioux City, IA | 15.1 mi |
| 51045 | Oyens, IA | 15.3 mi |
Questions about 51038
What is the ZIP+4 code for 51038?
51038 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 51038, you need to look up a specific street address to get them.
What city is 51038?
51038 is assigned to Merrill, Iowa, in Plymouth 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.