A switched receptacle (commonly called a half-hot or switch-controlled outlet) uses a wall switch to control one or both halves of a standard duplex receptacle. This is heavily used in living rooms and bedrooms to satisfy NFPA 70 (NEC) lighting requirements where overhead fixtures aren't present. The direct answer for wiring a standard half-hot outlet is: break the brass tab on the hot side of the receptacle, land the always-hot black wire on one brass screw, land the switched-hot red wire on the other brass screw, and tie the white neutrals to the silver screws. Use 14 AWG wire on a 15A breaker, or 12 AWG on a 20A breaker.
Tools, Materials, and Device Ratings
Before pulling any wire, ensure your materials match the circuit breaker rating. Never put 14 AWG wire on a 20A breaker, and never use a 15A receptacle on a 20A circuit unless it is a duplex (which is legally permitted by NEC 210.21(B)(3), but a 20A receptacle is better practice for high-draw loads).
Tool List
- Non-Contact Voltage Tester (NCVT): For initial dead-circuit verification (e.g., Klein NCVT-3).
- Digital Multimeter (DMM): For confirming 0V before touching wires and testing 120V post-installation.
- Wire Strippers: Rated for 14-10 AWG solid copper.
- Needle-Nose Pliers: For breaking the receptacle tab and forming wire hooks.
- Torque Screwdriver: Calibrated to inch-pounds. Standard 15A/20A devices require roughly 14 lb-in for 14 AWG and 16 lb-in for 12 AWG to prevent thermal loosening.
Materials
- Cable: 14/2 NM-B (from panel to receptacle) and 14/3 NM-B (from receptacle to switch). If on a 20A circuit, upgrade to 12/2 and 12/3 NM-B.
- Receptacle: 15A or 20A Spec-Grade duplex receptacle (e.g., Leviton 5262 or Hubbell 5262). Do not use builder-grade push-in (backstab) receptacles for switched loops; the arcing from switching loads degrades backstab connections rapidly.
- Switch: Single-pole 15A/20A toggle or rocker switch (e.g., Leviton 5601).
Terminal Mapping and Load Specifications
The table below maps exactly where every wire lands for a modern half-hot configuration. Note that under current NEC cycles (including 2023 and 2026 adoptions), a neutral conductor must be present at the switch box to accommodate future smart switches or timers. This is why we use 14/3 NM-B for the switch loop instead of the older 14/2 method.
| Wire Color | Function | Receptacle Terminal | Switch Terminal | AWG & Breaker Rating |
|---|---|---|---|---|
| Black (Line) | Always Hot | Brass (Bottom Half) | Brass (Bottom / Line) | 14 AWG (15A) / 12 AWG (20A) |
| Red (Load) | Switched Hot | Brass (Top Half) | Brass (Top / Load) | 14 AWG (15A) / 12 AWG (20A) |
| White (Neutral) | Return Current | Silver (Both Halves) | Not Used (Capped) | 14 AWG (15A) / 12 AWG (20A) |
| Bare/Green | Equipment Ground | Green Ground Screw | Green Ground Screw | 14 AWG (15A) / 12 AWG (20A) |
Mains Safety and Preparation
- De-energize: Turn off the specific 15A or 20A branch circuit breaker supplying the room.
- Initial Test: Use your NCVT on the existing outlet or switch to confirm the absence of voltage.
- Multimeter Verification: Set your DMM to AC Volts (V~). Measure from the existing black (hot) wire to the bare ground wire. The reading must be exactly 0.0V. Measure black to white (neutral); it must also read 0.0V.
- Prep the Boxes: Ensure your old-work or new-work boxes are deep enough. A standard switch box with 14/3 entering and leaving requires adequate cubic inch volume (minimum 18 cubic inches for 14 AWG with internal clamps and devices, per NEC 314.16).
Step-by-Step Switched Receptacle Wiring
This procedure assumes power enters the receptacle box first, and a 14/3 NM-B cable runs from the receptacle box to the switch box. We are wiring the top half of the receptacle to be switched, and the bottom half to be always-hot.
- Break the Hot Tab: Look at the side of the duplex receptacle with the brass-colored screws. You will see a small brass fin (tab) connecting the top and bottom screws. Use your needle-nose pliers to grip this tab and bend it back and forth until it snaps off. Do not break the silver tab on the neutral side.
- Ground the Receptacle: Form a hook in the bare copper ground wire from the panel and land it on the green ground screw on the receptacle. Tighten to 14 lb-in. Splice a 6-inch bare copper pigtail to this ground wire and run it to the metal box (if using a metal box) or cap it if using plastic.
- Land the Neutrals: Take the white (neutral) wire from the panel and land it on the top silver screw. Take the white (neutral) wire from the 14/3 cable heading to the switch and land it on the bottom silver screw. The silver tab remains intact, bonding both halves.
- Connect the Always-Hot: Take the black (hot) wire from the panel and land it on the bottom brass screw. This half of the outlet will now have constant power.
- Connect the Switched-Hot: Take the red wire from the 14/3 cable and land it on the top brass screw. This half will only receive power when the switch is closed.
- Terminate the Switch Box: At the switch, connect the bare copper ground to the green switch screw. Connect the black wire of the 14/3 cable to the bottom brass screw on the switch (Line). Connect the red wire of the 14/3 cable to the top brass screw on the switch (Load).
- Park the Switch Neutral: Because modern code requires a neutral at the switch box, the white wire in the 14/3 cable is present but unused for a standard mechanical toggle. Cap this white wire with a yellow or orange wire nut. Do not connect it to the switch.
Verify and Test with a Multimeter
Before pushing the devices into the boxes and screwing on the faceplates, you must verify the wiring under load conditions. For safety and OSHA compliance regarding energized testing, keep your hands clear of bare conductors.
- Turn the breaker back ON at the panel.
- Ensure the wall switch is in the OFF position.
- Set your DMM to AC Volts. Insert the probes into the bottom half of the receptacle (Hot to Neutral). Expected reading: 114V to 126V (nominal 120V).
- Insert the probes into the top half of the receptacle (Hot to Neutral). Expected reading: 0V (or a negligible ghost voltage under 2V).
- Flip the wall switch to the ON position.
- Measure the top half again. Expected reading: 114V to 126V.
- Measure Neutral to Ground at both halves. Expected reading: Less than 1.5V. If you read high voltage here, you have an open neutral or a miswired ground.
The Most Common Botch and Its Symptom
The single most common mistake DIYers make with switched receptacle wiring is failing to break the brass break-off tab on the hot side of the receptacle.
The Symptom: If you forget to snap off this tab, the always-hot black wire and the switched-hot red wire become physically bonded together through the receptacle's internal brass strap. When you turn the breaker on, one of two things will happen:
- Scenario A (Switch OFF): The always-hot back-feeds through the receptacle strap, into the red wire, and down to the switch. Both the top and bottom halves of the outlet will remain constantly hot, completely defeating the purpose of the switch.
- Scenario B (Switch ON): If the wiring is reversed or crossed at the switch, turning the switch ON will create a direct phase-to-phase or hot-to-hot dead short, instantly tripping the 15A or 20A breaker with a loud pop.
The Fix: Turn the breaker off, pull the receptacle out, and inspect the brass side. If the tab is still intact, remove it with pliers. Always visually verify the gap between the top and bottom brass screws before energizing the circuit. Additionally, ensure you are using the side-wire screw terminals rather than the push-in backstabs; backstabs are notorious for failing under the repeated thermal expansion and contraction caused by switching inductive loads like lamps and fans.
For more advanced configurations, such as wiring a fully switched receptacle (where both halves are controlled by the switch) or integrating smart home relays, consult the manufacturer's specific wiring diagrams and your local electrical inspector to ensure compliance with current NEC articles regarding switching and neutral requirements.
