When to call an electrician

Replacing a switch, an outlet or a fixture on wiring that is already there is a job many homeowners do. These are the ones that are not.

Call for these jobs

Anything inside the main panel, and adding or replacing breakers
New circuits, and new 240 V loads like a dryer, range, hot tub or EV charger
A service upgrade or a subpanel
Wiring outdoors or underground

Call when you see these

Aluminum branch wiring: dull silver wire on 15 and 20 amp circuits, common in homes built from about 1965 to 1973. It needs special connectors.
Knob-and-tube or cloth wiring with crumbling insulation.
Heat: warm switch plates or outlets, a burning smell, scorch marks or melted plastic.
A breaker that keeps tripping after you unplug things, or lights that flicker across the house.
Wires you cannot identify: more wires than any diagram shows, or anything still live with the breaker off.

Permits

Many places let homeowners replace a device in their own home without a permit, and require one for new circuits or new wiring. Some require a licensed electrician for all of it. Your local building department decides; a call or their website answers it in minutes.

If you are unsure, stop. A wiring mistake can work fine for years and still start a fire.