Do I need a permit for ev charger installation in Dallas County (Unincorporated)?

Most likely yes. Ev charger installation usually requires a permit in Texas. Confirm the specifics with Dallas County (Unincorporated).

TDLR licenses electricians, but the permit and inspection for a new 240-volt circuit are handled locally. Occupations Code 1305.201 lets a city require inspections by ordinance and adopt local amendments to the National Electrical Code, and electrical work inside city limits must follow local ordinances. Electrical work in Texas must be done by a licensed person unless an exemption applies. The homeowner exemption in Occupations Code 1305.003(a)(6) covers only work not specifically regulated by a municipal ordinance, in a dwelling the person owns and lives in. In an unincorporated area, electrical work must still meet standards at least as stringent as the state electrical code (Occupations Code 1305.201(e)), and TDLR states that a license is required there too. This installation adds a 240-volt circuit or a hardwired charger, or changes the electrical panel. New circuits and panel work are electrical work that normally needs an electrical permit and inspection wherever an electrical permit program exists. A panel upgrade or new service usually also involves your electric utility, which may need to disconnect and reconnect power, so call them early. Many places require a licensed electrician for this work. Where a homeowner may do their own wiring, the permit and inspection still apply.