ZIP Code 99603 — Homer, AK
99603 is a standard (street delivery) ZIP code serving Homer, Alaska, in Kenai Peninsula 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 99603 at a glance
| ZIP code | 99603 |
|---|---|
| Primary city | Homer |
| State | Alaska (AK) |
| County | Kenai Peninsula FIPS 02122 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Anchorage |
| Population | 11,693 |
| Coordinates | 59.523640, -151.228550 |
How ZIP+4 works in 99603
The four digits after the hyphen encode a delivery segment inside 99603. 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 99603 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 99603.
| ZIP | City | Distance |
|---|---|---|
| 99663 | Seldovia, AK | 16.5 mi |
| 99556 | Anchor Point, AK | 25.6 mi |
| 99639 | Ninilchik, AK | 32.9 mi |
Questions about 99603
What is the ZIP+4 code for 99603?
99603 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 99603, you need to look up a specific street address to get them.
What city is 99603?
99603 is assigned to Homer, Alaska, in Kenai Peninsula 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.