ZIP code 78664 covers Round Rock, Texas in Williamson County. This area is served by 64 utility providers across 6 categories. The average residential electricity rate here is 15.7¢/kWh. 52% of households use electricity as their primary heating fuel.
Estimated monthly utility costs
$328/month
Cost estimates from U.S. Census ACS 5-year data · Shorter bar = lower cost
Electric
Natural Gas
Water
Sewer
Trash & Recycling
Internet
Nearby ZIP codes
Frequently asked questions
How do I set up utilities when moving to 78664?
Contact each provider separately before your move-in date. Start with electric (Austin Energy) and gas (Atmos Energy Corporation, (888) 286-6700) since those typically need a few business days to activate. Water and sewer are often handled with one call to your local utility. Set up internet last since it may require an installation visit.
How much do utilities cost per month in 78664?
Total estimated monthly costs are around $327, which is about $56 less than the national average. Electricity is the biggest expense at roughly $175/month. Natural gas runs about $125. Water and sewer combined are around $28. Costs vary by home size, usage, and season. Estimates from U.S. Census ACS data.
Is electricity expensive in 78664?
Electricity costs in Round Rock, TX are close to the national average. Compared to Texas overall, rates here are about 15% higher. Based on 2023 NREL residential electricity rate data.
What internet providers are available in 78664?
Round Rock, TX has strong broadband coverage. Providers include AT&T (Fiber / DSL / Fixed Wireless up to 5,000 Mbps), Astound Broadband (Cable / Fiber / DSL up to 1,500 Mbps), Brightspeed (DSL), Google Fiber (Fiber up to 8,000 Mbps), Hotwire Communications (Fiber up to 5,000 Mbps). Availability varies by street address. Based on FCC Broadband Data Collection filings.
What county is 78664 in?
ZIP code 78664 is in Williamson County, Texas.
Disclaimer: Provider information is sourced from federal databases including HIFLD, EPA SDWIS, FCC Broadband Data, and EIA-861. Utility cost estimates are from the U.S. Census Bureau American Community Survey 5-Year Estimates. Electric rates are based on 2023 NREL data. Coverage areas are approximate and may not reflect recent changes. Please verify directly with your provider.
Data sources: U.S. Census Bureau, NREL, EIA-861, HIFLD, EPA, FCC. Last updated: April 2026.