ZIP Code 78879 — Rio Frio, TX
78879 is a standard (street delivery) ZIP code serving Rio Frio, Texas, in Real 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 78879 at a glance
| ZIP code | 78879 |
|---|---|
| Primary city | Rio Frio |
| State | Texas (TX) |
| County | Real FIPS 48385 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 184 |
| Coordinates | 29.643500, -99.717330 |
How ZIP+4 works in 78879
The four digits after the hyphen encode a delivery segment inside 78879. 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 78879 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 78879.
| ZIP | City | Distance |
|---|---|---|
| 78838 | Concan, TX | 7.5 mi |
| 78873 | Leakey, TX | 11.5 mi |
| 78884 | Utopia, TX | 13.5 mi |
| 78833 | Camp Wood, TX | 15.8 mi |
| 78885 | Vanderpool, TX | 16.3 mi |
| 78881 | Sabinal, TX | 21.3 mi |
| 78828 | Barksdale, TX | 21.6 mi |
| 78801 | Uvalde, TX | 21.7 mi |
| 78883 | Tarpley, TX | 24 mi |
| 78870 | Knippa, TX | 24.6 mi |
| 78055 | Medina, TX | 26.8 mi |
| 78024 | Hunt, TX | 28 mi |
Questions about 78879
What is the ZIP+4 code for 78879?
78879 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 78879, you need to look up a specific street address to get them.
What city is 78879?
78879 is assigned to Rio Frio, Texas, in Real 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.