ZIP code 78665
Where is ZIP code 78665?
Round Rock, Texas
Williamson County · Standard ZIP code
ZIP code 78665 belongs to Round Rock, Texas in Williamson County. 78665 is a standard ZIP code, so it covers street addresses as well as PO Boxes. It is in the Central Time zone and uses area codes 512 and 737. About 66,171 people live in the 78665 area, where the median household income is $122,680. The closest ZIP codes are 78664 (Round Rock, 0 mi north), 78681 (Round Rock, 0.8 mi southwest) and 78717 (Austin, 4.8 mi west).
| ZIP code | 78665 |
|---|---|
| Type | Standard ZIP code for street addresses and PO Boxes |
| Status | Active |
| City | Round Rock |
| State | Texas (TX) |
| County | Williamson County |
| Time zone | Central Time · now |
| Area codes | 512, 737 |
| Coordinates | 30.5145, -97.668 map |
| 3-digit prefix | 786 |
Population and income in 78665
| Population | 66,171 · higher than 97% of Texas ZIP codes |
|---|---|
| People per square mile | 2,748 · higher than 81% of Texas ZIP codes |
| Median age | 35.5 years · lower than 67% of Texas ZIP codes |
| Men / women | 50% / 50% |
| Median household income | $122,680 · higher than 93% of Texas ZIP codes |
| Income per person | $56,191 |
| Below the poverty line | 4.7% |
| Bachelor’s degree or higher | 54% of adults 25+ |
| Median home value | $474,100 · higher than 92% of Texas ZIP codes |
| Median rent | $1,938 a month |
| Housing units | 25,598 |
| Households | 24,162 (2.73 people on average) |
| Owners / renters | 61% / 39% |
| Land area | 24.08 sq mi (plus 0.36 sq mi of water) |
Source: U.S. Census Bureau, American Community Survey 5-year estimates (2020–2024) for ZIP Code Tabulation Area 78665. Census ZIP areas are close to, but not exactly the same as, USPS delivery areas.
ZIP codes near 78665
| ZIP code | City | Distance | Type |
|---|---|---|---|
| 78664 | Round Rock, TX | 0 mi N | Standard |
| 78681 | Round Rock, TX | 0.8 mi SW | Standard |
| 78717 | Austin, TX | 4.8 mi W | Standard |
| 78764 | Austin, TX | 4.8 mi S | PO Box only |
| 78651 | Mc Neil, TX | 5 mi SW | PO Box only |
| 78728 | Austin, TX | 5.1 mi S | Standard |
| 78660 | Pflugerville, TX | 5.5 mi SE | Standard |
| 78691 | Pflugerville, TX | 5.9 mi SE | PO Box only |
| 78634 | Hutto, TX | 6 mi E | Standard |
| 78727 | Austin, TX | 6.9 mi SW | Standard |
| 78729 | Austin, TX | 7.4 mi SW | Standard |
| 78627 | Georgetown, TX | 8.2 mi N | PO Box only |
Straight-line distance between ZIP code center points. Find every ZIP code within 10 miles of 78665 or measure the distance to another ZIP code.
How to address mail to 78665
123 MAIN ST
ROUND ROCK TX 78665
Put the city, the two-letter state code and the ZIP code on the last line. Adding the 4-digit ZIP+4 code (78665-XXXX) helps mail sort faster but isn’t required.
Other ZIP codes in Round Rock, TX
All Round Rock ZIP codes with population and income →
Questions
- What city is ZIP code 78665?
- 78665 is a Round Rock, Texas ZIP code.
- What county is 78665 in?
- ZIP code 78665 is in Williamson County, Texas.
- What time zone is ZIP code 78665 in?
- 78665 is in the Central Time zone (America/Chicago).
- What area code is 78665?
- Phone numbers in ZIP code 78665 use area codes 512 and 737.
- What is the population of ZIP code 78665?
- About 66,171 people live in ZIP code 78665, according to the Census Bureau’s American Community Survey (2020–2024).
- What is the median income in 78665?
- The median household income in 78665 is $122,680 a year, higher than 93% of Texas ZIP codes.
- What ZIP codes are near 78665?
- The nearest ZIP codes to 78665 are 78664 (Round Rock, 0 miles), 78681 (Round Rock, 0.8 miles), 78717 (Austin, 4.8 miles) and 78764 (Austin, 4.8 miles).