Jurisdiction Basics
Where You Live in Williamson County — City, ETJ, or Unincorporated — Matters
Your property's location — inside a city, in the city's extraterritorial jurisdiction, or in unincorporated county land — determines which rules and services apply to you.
In Texas, cities can reach beyond their limits into a surrounding buffer zone called an extraterritorial jurisdiction, or ETJ. Think of the ETJ as a ring of land just outside the city. In Williamson County, cities like Georgetown, Round Rock, Cedar Park, and Leander all have large ETJs.
If your property sits in an ETJ, city rules can apply to things like land use and building. You may not pay city taxes or get city services, but city planning rules still reach you.
Outside all ETJs is unincorporated county land. There, only Williamson County's rules apply — not any city's. Short-term rental rules, building permits, and which utility serves you can all differ based on your exact location. Use the county's GIS maps at wilcotx.gov to look up your property's location before you buy or build.
Source to confirm: Williamson County — GIS Maps and Data