ZIP Code 18843 — South Montrose, PA
18843 is a standard (street delivery) ZIP code serving South Montrose, Pennsylvania, in Susquehanna 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 18843 at a glance
| ZIP code | 18843 |
|---|---|
| Primary city | South Montrose |
| State | Pennsylvania (PA) |
| County | Susquehanna FIPS 42115 |
| ZIP type | Standard (street delivery) |
| Time zone | America/New_York |
| Population | 345 |
| Coordinates | 41.804460, -75.894160 |
How ZIP+4 works in 18843
The four digits after the hyphen encode a delivery segment inside 18843. 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 18843 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 18843.
| ZIP | City | Distance |
|---|---|---|
| 18801 | Montrose, PA | 3 mi |
| 18816 | Dimock, PA | 4.5 mi |
| 18844 | Springville, PA | 7.8 mi |
| 18826 | Kingsley, PA | 8.7 mi |
| 18824 | Hop Bottom, PA | 8.9 mi |
| 18834 | New Milford, PA | 9.7 mi |
| 18823 | Harford, PA | 10.6 mi |
| 18818 | Friendsville, PA | 10.9 mi |
| 18822 | Hallstead, PA | 11 mi |
| 18828 | Lawton, PA | 11.2 mi |
| 18630 | Meshoppen, PA | 11.9 mi |
| 18812 | Brackney, PA | 12.2 mi |
Questions about 18843
What is the ZIP+4 code for 18843?
18843 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 18843, you need to look up a specific street address to get them.
What city is 18843?
18843 is assigned to South Montrose, Pennsylvania, in Susquehanna 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.