ZIP Code 78957 — Smithville, TX
78957 is a standard (street delivery) ZIP code serving Smithville, Texas, in Bastrop 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 78957 at a glance
| ZIP code | 78957 |
|---|---|
| Primary city | Smithville |
| State | Texas (TX) |
| County | Bastrop FIPS 48021 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 10,543 |
| Coordinates | 30.012790, -97.174810 |
How ZIP+4 works in 78957
The four digits after the hyphen encode a delivery segment inside 78957. 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 78957 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 78957.
| ZIP | City | Distance |
|---|---|---|
| 78963 | West Point, TX | 10.6 mi |
| 78602 | Bastrop, TX | 12.1 mi |
| 78949 | Muldoon, TX | 13.4 mi |
| 78659 | Paige, TX | 13.7 mi |
| 78953 | Rosanky, TX | 15.2 mi |
| 78662 | Red Rock, TX | 16.7 mi |
| 78942 | Giddings, TX | 18.1 mi |
| 78945 | La Grange, TX | 18.3 mi |
| 78941 | Flatonia, TX | 18.7 mi |
| 78612 | Cedar Creek, TX | 19.6 mi |
| 78650 | Mcdade, TX | 20.3 mi |
| 78959 | Waelder, TX | 23 mi |
Questions about 78957
What is the ZIP+4 code for 78957?
78957 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 78957, you need to look up a specific street address to get them.
What city is 78957?
78957 is assigned to Smithville, Texas, in Bastrop 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.