ZIP Code 78642 — Liberty Hill, TX
78642 is a standard (street delivery) ZIP code serving Liberty Hill, Texas, in Williamson 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 78642 at a glance
| ZIP code | 78642 |
|---|---|
| Primary city | Liberty Hill |
| State | Texas (TX) |
| County | Williamson FIPS 48491 |
| ZIP type | Standard (street delivery) |
| Time zone | America/Chicago |
| Population | 26,434 |
| Coordinates | 30.694600, -97.940870 |
How ZIP+4 works in 78642
The four digits after the hyphen encode a delivery segment inside 78642. 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 78642 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 78642.
| ZIP | City | Distance |
|---|---|---|
| 78605 | Bertram, TX | 8.3 mi |
| 78641 | Leander, TX | 9.5 mi |
| 78633 | Georgetown, TX | 11.4 mi |
| 78628 | Georgetown, TX | 12.1 mi |
| 76527 | Florence, TX | 13.1 mi |
| 78613 | Cedar Park, TX | 14.8 mi |
| 78608 | Briggs, TX | 16.5 mi |
| 78645 | Leander, TX | 16.9 mi |
| 78681 | Round Rock, TX | 17.1 mi |
| 78717 | Austin, TX | 18 mi |
| 78654 | Marble Falls, TX | 18.1 mi |
| 78726 | Austin, TX | 19.2 mi |
Questions about 78642
What is the ZIP+4 code for 78642?
78642 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 78642, you need to look up a specific street address to get them.
What city is 78642?
78642 is assigned to Liberty Hill, Texas, in Williamson 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.