The Extraterritorial Jurisdiction (ETJ) is the unincorporated land within five miles of the City of San Antonio (and other incorporated cities) boundaries and includes all unincorporated territory that is not located in another city’s municipal boundary or ETJ. It is the area in which the City of San Antonio (and other incorporated cities) is/are the only authorized entity able to annex land. The ETJ enables the city to extend regulations to adjacent land where development can affect the quality of life within the city. ETJ regulations help to ensure that subdivisions that may be annexed in the future meet certain minimum standards. The claim to be effective in the external territory (except by the exercise of force) must be agreed with the legal authority in the external territory, or with a legal authority which covers both territories. When qualfied, ETJ usually refers to such as agreed jurisdiction, or it will be called "claimed ETJ".

Note from City of San Antonio Open Data Portal: This is a graphical polygon dataset depicting the polygon boundaries of Cities within Bexar County Texas and Surrounding Counties. (excluding San Antonio)Updated per Ordinance No. 564, No. 565, and No. 567 on April 9, 2015 extending the Helotes City limits with the annexation of four parcels of vacant property known as Bricewood Subdivision. Updated previously per Resolution No 2012-007-R From the City of Somerset .Updated per ordinance 2014-09-04-0657 (Savano Park ETJ ONLY release)Updated per ordinance 2014-09-04-0658 (Live Oak City Limit release)Updated per ordinance 2014-08-21-0614 (Fair Oaks Ranch ETJ ONLY release.