ZIP Code 55803 — Duluth, MN
55803 is a standard (street delivery) ZIP code serving Duluth, Minnesota, in St. Louis 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 55803 at a glance
| ZIP code | 55803 |
|---|---|
| Primary city | Duluth |
| State | Minnesota (MN) |
| County | St. Louis FIPS 27137 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 17,662 |
| Coordinates | 47.033980, -92.071040 |
How ZIP+4 works in 55803
The four digits after the hyphen encode a delivery segment inside 55803. 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 55803 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 Duluth
Nearby ZIP codes
Showing the closest twelve. See every ZIP code within 25 miles of 55803.
| ZIP | City | Distance |
|---|---|---|
| 55804 | Duluth, MN | 9.3 mi |
| 55609 | Knife River, MN | 14.3 mi |
| 55814 | Duluth, MN | 14.9 mi |
| 55717 | Canyon, MN | 14.9 mi |
| 55811 | Duluth, MN | 15.2 mi |
| 55812 | Duluth, MN | 15.3 mi |
| 55805 | Duluth, MN | 16.1 mi |
| 55724 | Cotton, MN | 17.4 mi |
| 55806 | Duluth, MN | 18.5 mi |
| 55802 | Duluth, MN | 19.4 mi |
| 55779 | Saginaw, MN | 20 mi |
| 55807 | Duluth, MN | 21.1 mi |
Questions about 55803
What is the ZIP+4 code for 55803?
55803 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 55803, you need to look up a specific street address to get them.
What city is 55803?
55803 is assigned to Duluth, Minnesota, in St. Louis 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.