I would like to add a ceiling light to a bedroom that currently does not have one. It has a switch which controls a receptacle. I would like to convert that receptacle to always be hot and add the new light to the current switch location. I plan to replace the switch with a dimmer switch too.

Current Wiring as follows:

Switch: two cables coming in. One is 2 wire(black/white)+ground and the other is 3 wire(black/white/red)+ ground. switch

Receptacle: two cables coming in. One is 2 wire(black/white)+ground and the other is 3 wire(black/white/red)+ ground.


I’ve already run a new 3 wire cable from ceiling light location to the wall switch.

Any guidance would be greatly appreciated!

Thank you Felix

  • Box fill at switch: one 12/2, two 12/3, egc (+1), one device yoke (+2) = 11, 11*2.25 cu in per #12 conductor = 24.75 in³. That box is way overfilled. Maybe swap out with 4x4x1.5 with mud ring. Jan 2, 2022 at 1:41
  • Yes I was planning on swapping the box out with something bigger. That is a before picture, that box is no longer there. Thanks for the input! Jan 2, 2022 at 2:34

2 Answers 2


Remove the red wire from the switch, wirenut it to the black wires already at the switch location (not your new cable.) Now the outlet is unswitched. There are more complicated ways to do this, I advise this as the simplest.

Connect your new cable White to the whites in the switch box, and your new cable Red to the switch, where you removed the old red.

Cap off the new cable black, you don't need it right now. Connect the light fixture to white and red from that cable.

  • Thank you for your response! I’ll be taking the information you provided along with the other answer and get it connected in the morning. Still need to purchase the dimmer switch to finish it off. Jan 2, 2022 at 2:39

There are a few different ways things can be done. However, the good news is that it looks like all whites are neutral, all blacks are always hot and the one red wire is switched hot. In addition, you only have the red wire on the receptacle but not black, so it is not a split receptacle. You need to do the following:

Receptacle - Change from switched hot (red) to hot (black)

  • Remove the red wire from the receptacle. It will not be used any more, so cap it with a wire nut and a piece of electrical tape to make sure the wire nut stays on, as wire nuts are not (usually) designed for a single wire.

  • Remove the two black wires from wire nut and connect them to the two hot side screws on the receptacle. Do not use the backstabs - not as reliable and not meant for multiple uses. Alternatively...

  • Add a short 12 AWG (15A or 20A circuit) or 14 AWG (15A circuit) piece of black wire to the wire nut connecting the two black wires (you may want to use a fresh wire nut) and connect the other end to one of the hot side screws on the receptacle. Then do the same thing for the white wires - remove from the backstabs, add a short white pigtail and connect all three with a wire nut and put the other end of the pigtail on one of the receptacle neutral side screws.

Switch - Connect to new cable

  • Disconnect the old red wire and connect the new red wire to the switch. Cap the old red wire with a wire nut.

  • Add the new white wire to the existing group of white wires.

  • It isn't clear exactly what is going on with the black wires. You have two existing black wires, and a wire nut but it doesn't look like a typical pigtail. It looks like one wire loops around the screw and then ends in the wire nut together with the other wire. What you want is the old two black wires + the new black wire all in a wire nut along with a pigtail which goes to the switch.

With a simple/"dumb" switch, there is no difference between hot and switched hot - i.e., you can flip the wires to alternate screws and it will make no difference whatsoever. However, with a dimmer, smart switch, timer, motion sensor, etc. there often is a difference. In your case, it is pretty straightforward: black = hot ("in", "line"), red = switched hot ("out", "load").

Many fancier switches (but not all) will also require neutral. That is easy in your situation (often it is not easy at all) - just add a pigtail to the neutral bunch. Watch out for wire nut limits - the package should list how many wires you can include in each type of wire nut.

Ceiling fixture

Connect white to the neutral connection and connect red to the hot/switched hot connection. You won't use the black wire. This is based on the convention of "something other than black or white for switched hot, when practical." Note, however, that if someday you want to have a light and fan with separate switches, you can do that, using black for the light and red for the fan (or vice versa).

End result will be red wire between receptacle and switch boxes not used and black wire between switch and ceiling boxes not used.

  • Thank you for the detailed response! Yea not sure what the reasoning was with how they tied in the black wires in the switch box, definitely threw me off a bit as I’ve never seen it like that before. I’m removing the switch in the picture and replacing it with a dimmer switch, should be the same connections I would assume whether it’s a dimmer switch or toggle? Jan 2, 2022 at 2:36
  • One or two differences. I'll edit. Jan 2, 2022 at 2:38
  • Thanks for adding in the information for the dimmers, Very clear instructions! For the new cable coming from the light I assume I would tie in the ground to the existing grounds in the switch box, correct? Jan 2, 2022 at 2:57
  • 1
    All grounds always together and to metal boxes (which it appears you have). Many better quality switches & receptacles are designed to ground directly via the yoke when you have a grounded metal box, in which case you don't need to attach a ground wire to those devices (check the specs.) Jan 2, 2022 at 2:59

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