Wiring a GFCI Receptacle Plus a Light Switch: How Should It Go Together?
A user asked the app how to wire a GFCI receptacle and a light switch in the same box. There are three clean ways to do it, and the choice comes down to one question: do you want the light on GFCI protection or not?
Keep the light off GFCI protection
This is the usual choice for a bathroom or garage where a tripped receptacle should not kill the lights. Bring the incoming hot into the box and pigtail it: one tail to the GFCI LINE hot terminal, one tail to the switch. Pigtail the neutrals the same way, one to the GFCI LINE neutral, with the light's neutral spliced through. The switch leg goes out to the light. Nothing lands on the GFCI LOAD terminals, and the factory tape stays on them. The light works no matter what the receptacle does. This layout also satisfies the 404.2(C) requirement for a neutral at the switch location, since the neutral is present in the box.
Protect the light too
If the fixture is over a shower, or the AHJ or the fixture listing calls for GFCI protection, feed the switch from the GFCI LOAD side instead: incoming power to LINE, then a jumper from LOAD hot to the switch, switch leg out to the light, and the light neutral back to the LOAD neutral terminal. Everything downstream of LOAD gets protection, including the fixture. The tradeoff is that a trip at the receptacle darkens the room, which is exactly why NEC 2023 Section 210.8 protects receptacles and generally leaves lighting outlets alone in dwellings. Note that hydromassage tubs under 680.71 and some luminaires within a tub or shower zone per 410.10(D) carry their own GFCI or listing requirements, so read the fixture instructions before deciding.
Box fill and combination devices
Two devices, their yokes, conductors, and grounds add up fast under 314.16. A midsize single gang box with 12 AWG conductors, two yokes, and grounds often exceeds the volume of an old work box, so count it: each conductor is one volume unit, all grounds together are one, and each yoke counts as two units at the largest conductor size. When space is tight, a listed combination GFCI switch device puts both functions on one yoke, and most brands let you choose whether the switch side is protected. Wire per the leaflet in the box, because terminal layouts differ between manufacturers.