ZIP Code 52557 — Fairfield, IA
52557 is a standard (street delivery) ZIP code serving Fairfield, Iowa, in Jefferson 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 52557 at a glance
| ZIP code | 52557 |
|---|---|
| Primary city | Fairfield |
| State | Iowa (IA) |
| County | Jefferson FIPS 19101 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 685 |
| Coordinates | 41.020260, -91.966530 |
How ZIP+4 works in 52557
The four digits after the hyphen encode a delivery segment inside 52557. 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 52557 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.
Other ZIP codes in Fairfield
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 52557.
| ZIP | City | Distance |
|---|---|---|
| 52556 | Fairfield, IA | 2.1 mi |
| 52567 | Libertyville, IA | 8.2 mi |
| 52580 | Packwood, IA | 9.5 mi |
| 52533 | Batavia, IA | 9.6 mi |
| 52535 | Birmingham, IA | 10.7 mi |
| 52635 | Lockridge, IA | 11 mi |
| 52585 | Richland, IA | 11.7 mi |
| 52540 | Brighton, IA | 12.1 mi |
| 52651 | Stockport, IA | 13.7 mi |
| 52588 | Selma, IA | 14.9 mi |
| 52576 | Ollie, IA | 15.3 mi |
| 52554 | Eldon, IA | 15.4 mi |
Questions about 52557
What is the ZIP+4 code for 52557?
52557 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 52557, you need to look up a specific street address to get them.
What city is 52557?
52557 is assigned to Fairfield, Iowa, in Jefferson 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.