Single Pole Switch on Line Side, Outlet on Load Side
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In the line side box, remove one of the traveler wires from the 3-way switch. Using a wire connector, connect this traveler to the line wire and the wire that will connect to the common terminal of the 3-way switch.
In the load side box, remove the 3-way switch. Using a wire connector, connect the traveler wire from the switch in the line side box to the wire going to the light using a wire connector. Connect the other traveler wire (line) from the line side box to the outlet line terminal. Connect a neutral wire to the neutral terminal of the outlet.
Outlet on Load Side, Single Pole Switch on Line Side
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In the line side box, remove the 3-way switch. Using a wire connector, connect the line wire to one of the traveler wires and to a wire that connects to the line side of the outlet. Install a wire connector on the other traveler to make it a spare. Connect the neutral side of the outlet to a neutral wire.
In the load side box, remove the traveler spare wire from the switch and attach a wire connector to it.
Convert 3-way Switches to Single Pole Page 1
Convert 3-Way Switches to Single Pole Page 2