I have switched garbage disposal, like many people do. The switch is on a wall w/o any outlets. I'd like to convert the switch to a switch/outlet combo. I read that you shouldn't add an outlet to the dishwasher or disposal circuit so I figured I'd ask y'all.

Here are some facts:

  1. The dishwasher is hardwired.
  2. The garbage disposal is corded (not hardwired) and runs to an outlet under the sink. Nothing else is plugged into that outlet.
  3. I'm not sure if the dishwasher and disposal are on the same circuit. Or what else is on either circuit.
  4. I'm not sure what the amperage of either circuit is.

Here are my questions:

  1. As a general question, can I add an outlet to the garbage disposal switch?
  2. If yes, what considerations do I need to take into account? What questions would I need to know the answers to before proceeded? What would I need to change?
  3. If no, why not?

Thank y'all so much! Jason

  • You need to know if the dishwasher shares the circuit, and if there is a neutral available in the disposal switch box. Also, do you have room to turn that one-gang switch box into a two-gang box?
    – JPhi1618
    Jan 22, 2020 at 19:32
  • 1) There is a neutral in the switch box. 2) I'm planning on removing the switch box and replacing it with a 2 gang old work box. I'm planning on the new outlet being a GFCI since it's in the kitchen. 3) What if the dishwasher shares the circuit? Does that prevent me from adding the outlet? Jan 22, 2020 at 19:39

3 Answers 3


This should be fine*

There is not a restriction that a disposal must be on a dedicated circuit unless the manufacturer states that it must be. Unless you have a high-end beast of a commercial unit, it probably doesn't.

There are rules in the NEC on circuit sharing, and a "fixed" device like a disposal or dishwasher can't use any more than 50% of the circuit capacity if that circuit is to be shared with general purpose lighting/outlets.

What that means in your case is that if the dishwasher shares the circuit, it probably uses more than 50% because of the heater used for drying and water heating. I think that means you really shouldn't share it with the disposal either and it should be dedicated (so I normally see a dedicated circuit for them).

If the disposal is on it's own or already shared with other kitchen outlets, you are fine to add an outlet.

GFCI required

As you stated, a GFCI outlet is required, and that means you will need a two gang box. There are switch/outlet combos you could stuff into a single box, but not with GFCI (Link in comments, single gang switch/GFCI does exit), but you probably want more than a singe receptacle. Upgrade to a two gang (or three!) box and use a GFCI outlet.

  • 1
    I've a single gang switch/GFCI in my bathroom. homedepot.com/p/…
    – Phil G
    Jan 22, 2020 at 20:12
  • 1
    @PhilG, Cool - they come out with new stuff all the time. Good to know that exists!
    – JPhi1618
    Jan 22, 2020 at 20:15

Expanding on the comments here.

1) determine whether your dishwasher is on the same circuit. Turn breakers off & see what happens with each breaker, i.e. does the outlet stay live while the dishwasher goes down?

2) look up the amperage drawn by the dispos-all and any other items (dishwasher or anything else that share that breaker. Compare with breaker capacity.

3) If everything is copascetic, go ahead and add an outlet connected to the hot and neutral source side wires feeding the disposal switch. You'll need a larger receptacle box, and the usual array of wire nuts for connections, etc.


Just about a week ago I was asking the inspector several questions regarding helping my son build a house. During our discussion I mentioned I planned to put the garbage disposal outlet on the same circuit as some kitchen outlets (3 20 amp circuits for small appliances, so plenty of power). He said no way, a GD is a permanently installed appliance requiring it's own circuit. OK, I asked could I share it with a DW circuit. He was less committal on that, but repeated that all permanently installed appliances required their own circuit. So if this will be inspected, you'll want to check with your local inspector and get his/her input.

  • Ask him if a bath fan requires its own circuit. :) Jan 23, 2020 at 1:46
  • LOL, Thanks 3ph. I don't think a bath fan is considered an "appliance". But I get your drift, this stuff is getting carried away: Another run to the panel and a $50 AFCI breaker for a disposal that may get used for 2-3 minutes a day, max. Jan 23, 2020 at 6:25

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