ZIP Code 83605 — Caldwell, ID
83605 is a standard (street delivery) ZIP code serving Caldwell, Idaho, in Canyon 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 83605 at a glance
| ZIP code | 83605 |
|---|---|
| Primary city | Caldwell |
| State | Idaho (ID) |
| County | Canyon FIPS 16027 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Boise |
| Population | 41,325 |
| Coordinates | 43.664420, -116.651710 |
How ZIP+4 works in 83605
The four digits after the hyphen encode a delivery segment inside 83605. 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 83605 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 Caldwell
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 83605.
| ZIP | City | Distance |
|---|---|---|
| 83607 | Caldwell, ID | 5.6 mi |
| 83651 | Nampa, ID | 5.6 mi |
| 83644 | Middleton, ID | 6.7 mi |
| 83687 | Nampa, ID | 7.1 mi |
| 83669 | Star, ID | 8.4 mi |
| 83656 | Notus, ID | 8.5 mi |
| 83626 | Greenleaf, ID | 8.8 mi |
| 83646 | Meridian, ID | 11 mi |
| 83686 | Nampa, ID | 11.8 mi |
| 83676 | Wilder, ID | 13 mi |
| 83642 | Meridian, ID | 14 mi |
| 83616 | Eagle, ID | 15.2 mi |
Questions about 83605
What is the ZIP+4 code for 83605?
83605 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 83605, you need to look up a specific street address to get them.
What city is 83605?
83605 is assigned to Caldwell, Idaho, in Canyon 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.