ZIP Code 50591 — Thor, IA
50591 is a standard (street delivery) ZIP code serving Thor, Iowa, in Humboldt 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 50591 at a glance
| ZIP code | 50591 |
|---|---|
| Primary city | Thor |
| State | Iowa (IA) |
| County | Humboldt FIPS 19091 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 405 |
| Coordinates | 42.676830, -94.054780 |
How ZIP+4 works in 50591
The four digits after the hyphen encode a delivery segment inside 50591. 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 50591 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 50591.
| ZIP | City | Distance |
|---|---|---|
| 50516 | Badger, IA | 5.4 mi |
| 50594 | Vincent, IA | 6.3 mi |
| 50533 | Eagle Grove, IA | 7.5 mi |
| 50529 | Dakota City, IA | 8.1 mi |
| 50545 | Hardy, IA | 8.4 mi |
| 50542 | Goldfield, IA | 9 mi |
| 50548 | Humboldt, IA | 9.1 mi |
| 50577 | Renwick, IA | 13.1 mi |
| 50599 | Woolstock, IA | 13.9 mi |
| 50558 | Livermore, IA | 14.3 mi |
| 50501 | Fort Dodge, IA | 14.4 mi |
| 50582 | Rutland, IA | 14.9 mi |
Questions about 50591
What is the ZIP+4 code for 50591?
50591 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 50591, you need to look up a specific street address to get them.
What city is 50591?
50591 is assigned to Thor, Iowa, in Humboldt 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.