Find the last 4 digits (ZIP+4) for an address in 78663

ZIP 78663, Round Mountain, TX is filled in. Just type the street address.

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ZIP Code 78663 – Round Mountain, TX

Round Mountain, Texas · Blanco County · Central time

ZIP code78663
CityRound Mountain
StateTexas
CountyBlanco CountyTravis CountyHays CountyBurnet County
Population503
Time zoneCentral · local time
ZIP typeStandard (has a Census ZCTA area)
Land area108.48 sq mi
Center (lat, long)30.4155, -98.3117

Area codes in this area

512737830

These are the area codes that most often serve ZIP 78663 (including overlays). The exact area code depends on the phone number — landlines, mobiles and overlays can differ even on the same street.

Map

Nearby ZIP codes

78657 Horseshoe Bay · 9 mi78636 Johnson City · 9.6 mi78669 Spicewood · 11.4 mi78654 Marble Falls · 12.4 mi78620 Dripping Springs · 16.8 mi78639 Kingsland · 18.7 mi78635 Hye · 20.1 mi78645 Leander · 20.4 mi

About ZIP 78663

ZIP code 78663 is assigned to Round Mountain, Texas. It crosses 4 counties; most of its land is in Blanco County. Its Census area covers about 108.48 square miles of land. The closest neighboring ZIP is 78657 (Horseshoe Bay), about 9 miles away.

Every address in 78663 also has a 4-digit add-on code (ZIP+4) that points to a smaller delivery area. Use the box above to find it.

Sources: US Census Bureau (ZCTA, county relationship files), GeoNames (CC BY 4.0), NANPA via NumberResearch.org (CC BY 4.0). Map © OpenStreetMap contributors. ZIP areas are approximate. Population: U.S. Census Bureau, ACS 5-year estimates, 2024 (ZCTA). Data sources