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How many receptacles can I place on a 20 amp breaker if it's a 120 volt circuit? How many on a 15 amp circuit? I'm trying some DIY on my bathroom and bedroom. Help would be appreciated.

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There's no limit to the number of receptacles that can be on a circuit in a residential dwelling. Code does specify a minimum number of receptacles required in a room (NEC 210.52(A)), based on the length of the walls. The code does not, however, limit the number of receptacles per circuit.

In industrial/commercial spaces, 180 Volt-Amperes (VA) is used when calculating receptacle loads. This value is often used as a guideline in residential applications as well. For example, given a 15 ampere 120 volt circuit, you could have 10 receptacles @ 180 VA.

15 A * 120 V = 1800 VA
1800 VA / 180 VA = 10

So a 20 ampere 120 volt circuit, could have 13 receptacles @ 180 VA.

20 A * 120 V = 2400 VA
2400 VA / 180 VA = 13.333

These numbers are simply a guideline, and have no real meaning in residential dwelling units.


You will have to keep the bathroom and bedroom circuits separate, and the bathroom receptacles will have to be supplied by at least one 20 ampere branch circuit (NEC 210.11(C)(3)). So you'll need at least two, 20 ampere branch circuits. One for the bathroom receptacles, and one for the bedroom receptacles.

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I do see how the result of how many receptacles there can be safely on a 20 Amp at any given time... I also figured out A*V=W. Then, to figure out how many receptacles, divide your total watts by the number of amps * receptacles... since 120 V = 180 VA *10 = 1800VA. 20A * 120 = 2400VA ÷ 180VA ={13} recepts. Alright. Got it. I have a better understanding how to wire a 20 Amp circuit. but to be safe and you shouldn't want more than 8 receipts. on a 20 Amp circuit: 3 lamp boxes, 3 switch boxes, and 2 wall socket boxes.

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    This is almost certainly governed by the electrical code, and answering without referring to code is almost certainly incomplete or misleading. Nov 26, 2015 at 1:21
  • There's no formula like that, though you are welcome to cook one up, for your own use. You are allowed to have 30 receptacles on a single 15A circuit, in fact, that might be a reasonable thing to do for outlets intended for LED christmas lights or a bunch of cell phone charging stations at a convention center. Sep 10, 2016 at 21:22

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