ZIP Code 51637 — College Springs, IA
51637 is a standard (street delivery) ZIP code serving College Springs, Iowa, in Page 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 51637 at a glance
| ZIP code | 51637 |
|---|---|
| Primary city | College Springs |
| State | Iowa (IA) |
| County | Page FIPS 19145 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 171 |
| Coordinates | 40.620460, -95.118320 |
How ZIP+4 works in 51637
The four digits after the hyphen encode a delivery segment inside 51637. 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 51637 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 51637.
| ZIP | City | Distance |
|---|---|---|
| 51630 | Blanchard, IA | 4.2 mi |
| 51651 | Shambaugh, IA | 5 mi |
| 51631 | Braddyville, IA | 5.8 mi |
| 64445 | Elmo, MO | 6 mi |
| 51636 | Coin, IA | 6.9 mi |
| 51656 | Yorktown, IA | 8.1 mi |
| 64431 | Clearmont, MO | 9 mi |
| 51632 | Clarinda, IA | 9.5 mi |
| 64498 | Westboro, MO | 11.6 mi |
| 51647 | Northboro, IA | 11.9 mi |
| 64428 | Burlington Junction, MO | 12.4 mi |
| 51601 | Shenandoah, IA | 14.3 mi |
Questions about 51637
What is the ZIP+4 code for 51637?
51637 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 51637, you need to look up a specific street address to get them.
What city is 51637?
51637 is assigned to College Springs, Iowa, in Page 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.