Installing a Bathroom Vanity Light Fixture

Bathroom lighting sets the tone for your entire morning routine. A dim, flickering fixture or one installed at the wrong height leaves you squinting at the mirror and struggling with makeup, shaving, or basic grooming. A properly installed vanity light—positioned at eye level, rated for the moisture of a bathroom, and wired safely—transforms that space into something functional and honest. The fixture itself is usually straightforward to hang, but the electrical connection demands respect and attention. Get this right, and you'll have reliable light for years. Mess up the wiring, and you're looking at a fire hazard or a blown breaker.

1. Turn off power and test the circuit. Locate the breaker controlling the bathroom light circuit and flip it off. Test the old fixture with a lamp or phone flashlight to confirm power is dead. Use a non-contact voltage tester on the fixture terminals to double-check—if the tester lights up, the power is still on and you need to find the correct breaker.
2. Remove the old fixture. Unscrew and remove any glass shades, trim rings, or covers from the existing fixture. Unscrew the mounting bracket bolts holding the fixture to the wall box and gently pull the fixture away from the wall. Inside, you'll see three wires twisted together with wire nuts. Turn each wire nut counterclockwise and untwist the wires. Loosen the ground wire (bare copper) from the screw on the box if present.
3. Inspect the electrical box and patch the wall. Look inside the wall box where the old fixture was mounted. If it's loose, corroded, or damaged, tighten the mounting screws or replace the box entirely. If the old fixture left a large hole in the wall or the box is smaller than the new fixture's base, you may need to patch drywall or use a larger trim ring. Most new fixtures come with a trim ring that covers standard gaps.
4. Install the mounting bracket. Attach the new fixture's mounting bracket to the electrical box using the provided bolts. Most brackets slide or screw onto the box ears. Ensure the bracket is level before tightening fully. The bracket should sit flush against the wall with no gaps. Once level and tight, thread the fixture's ground wire (bare copper or green) around the ground screw on the box and tighten the screw.
5. Connect the wires. You'll have three wires from the wall (black, white, bare copper) and three from the new fixture (usually black, white, bare copper, or sometimes a green ground). Strip about half an inch of insulation from each wire if not already done. Twist the black wires together clockwise, twist the white wires together clockwise, and twist the bare copper wires together. Screw a wire nut onto each pair—black to black first, then white to white, then ground. Turn the nut until tight; the wires shouldn't pull apart with gentle tugging.
6. Tuck wires and secure the fixture. Gently push the connected wires back into the electrical box, coiling them loosely so they don't get pinched. Attach the fixture body to the mounting bracket using the provided screws or bolts. Tighten these screws evenly so the fixture sits flush against the wall. Ensure no wires are bent sharply or exposed.
7. Install shades and test. Attach any glass shades, diffusers, or trim rings according to the fixture's instructions. Restore power at the breaker and flip the light switch on. The fixture should light immediately and smoothly. Check that all bulbs illuminate (if it's a multi-bulb fixture) and that there are no buzzing, flickering, or unusual sounds.
8. Caulk around the trim ring if needed. If there's a visible gap between the trim ring and the wall, apply a thin bead of paintable caulk around the perimeter. Smooth it with a wet finger and let it dry for the time specified on the caulk tube. Paint to match if necessary. This keeps moisture and dust from sneaking behind the fixture.