ZIP Code 48189 — Whitmore Lake, MI
48189 is a standard (street delivery) ZIP code serving Whitmore Lake, Michigan, in Washtenaw 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 48189 at a glance
| ZIP code | 48189 |
|---|---|
| Primary city | Whitmore Lake |
| State | Michigan (MI) |
| County | Washtenaw FIPS 26161 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Detroit |
| Population | 13,893 |
| Coordinates | 42.411370, -83.783060 |
How ZIP+4 works in 48189
The four digits after the hyphen encode a delivery segment inside 48189. 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 48189 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 48189.
| ZIP | City | Distance |
|---|---|---|
| 48139 | Hamburg, MI | 3.1 mi |
| 48143 | Lakeland, MI | 4.6 mi |
| 48116 | Brighton, MI | 6.4 mi |
| 48178 | South Lyon, MI | 6.5 mi |
| 48105 | Ann Arbor, MI | 6.8 mi |
| 48130 | Dexter, MI | 7.2 mi |
| 48169 | Pinckney, MI | 9.2 mi |
| 48109 | Ann Arbor, MI | 9.3 mi |
| 48165 | New Hudson, MI | 10.5 mi |
| 48104 | Ann Arbor, MI | 10.7 mi |
| 48114 | Brighton, MI | 10.9 mi |
| 48103 | Ann Arbor, MI | 11 mi |
Questions about 48189
What is the ZIP+4 code for 48189?
48189 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 48189, you need to look up a specific street address to get them.
What city is 48189?
48189 is assigned to Whitmore Lake, Michigan, in Washtenaw 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.