To wire a switched outlet (half-hot receptacle), you must break the connecting brass tab on the hot side of a 15A or 20A duplex receptacle. Connect the always-hot black wire to the top brass screw, the switched-hot red wire to the bottom brass screw, the neutral white wire to the silver screw, and the bare copper ground to the green grounding screw. Use 14 AWG copper wire for 15A circuits and 12 AWG for 20A circuits.
Working with 120V AC mains voltage carries a risk of fatal shock or arc flash. Before opening any junction box or receptacle, you must de-energize the circuit at the main panel. Lock out or tag the breaker to prevent accidental re-energizing. Always verify the circuit is dead using a known-working non-contact voltage tester (NCVT) and a digital multimeter before touching any conductors. NEC-style guidance is provided here; your local Authority Having Jurisdiction (AHJ) has final authority on code compliance and may require a licensed electrician for this work.
Tools, Materials, and Device Ratings
Split-wiring a receptacle requires specific cable configurations and properly rated components. Do not use standard push-in backstab connections for this setup; the internal spring contacts can fail under continuous lamp loads, leading to arcing. Use side-wiring (terminal screws) or screw-and-clamp back-wiring.
- Receptacle: 15A Tamper-Resistant (TR) Duplex Receptacle (e.g., Leviton T5252 or Eaton TR20R). Use a 20A TR receptacle (e.g., Leviton T5262) if the circuit breaker is 20A.
- Wire Gauge: 14 AWG copper for 15A breakers; 12 AWG copper for 20A breakers. Never put 14 AWG wire on a 20A breaker.
- Cable: 14/3 or 12/3 NM-B (Romex) cable. The third wire (red) is required to carry the switched hot from the wall switch to the receptacle.
- Wire Strippers: Precision strippers (e.g., Klein Tools 11055) calibrated for 14 and 12 AWG to avoid nicking the copper conductor.
- Testers: CAT III rated digital multimeter and a Non-Contact Voltage Tester (NCVT).
- Pliers: Needle-nose pliers for cleanly snapping the breakaway brass tab.
The Most Common Botch (and Its Symptom)
The most frequent error in switched outlet wiring is failing to break the hot-side brass tab. Duplex receptacles ship with a small metal fin connecting the top and bottom brass screws. If you leave this tab intact and wire the black and red wires to the brass screws, both halves of the outlet will remain constantly hot. The wall switch will do absolutely nothing, and you will be left wondering why your lamp won't turn off.
A far more dangerous botch is accidentally breaking the silver neutral-side tab. The neutral tab should remain completely intact. If you snap the silver tab, the return path for the current is broken. Depending on how the upstream neutrals are tied, this will either result in a dead outlet (open neutral) or, if a multi-wire branch circuit (MWBC) is involved, it can cause a severe voltage imbalance that will instantly destroy connected electronics and trip the main breaker. Always double-check that you are snapping the brass (hot) tab, not the silver (neutral) tab.
Step-by-Step Switched Outlet Wiring Procedure
Follow these termination steps exactly. Ensure your circuit breaker is OFF and verified dead before beginning.
- Prepare the Conductors: Strip exactly 3/4 inch (19mm) of insulation from the black, red, and white wires using your wire strippers. Do not nick the copper. If the wire is stranded, twist it tightly; if solid, ensure it is straight.
- Break the Brass Tab: Locate the two brass (dark colored) screws on the hot side of the receptacle. Use your needle-nose pliers to grip the small metal tab between the top and bottom brass screws. Bend it back and forth until it snaps off cleanly. Leave the silver side tab completely intact.
- Terminate the Ground Wire: Form a clockwise hook in the bare copper ground wire. Loop it around the green grounding screw at the bottom of the receptacle. Tighten the screw until the wire is pulled snug against the metal strap. (Leviton specifies 14 in-lbs of torque for terminal screws; snug plus a quarter-turn is a good field rule).
- Terminate the Neutral Wire: Form a clockwise hook in the white neutral wire. Connect it to either of the silver screws on the neutral side. Because the silver tab is intact, it does not matter which silver screw you use, but the top silver screw is standard practice.
- Terminate the Always-Hot Wire: Form a clockwise hook in the black always-hot wire. Connect it to the top brass screw. This ensures the top half of the receptacle has constant 120V power for devices like phone chargers or vacuums.
- Terminate the Switched-Hot Wire: Form a clockwise hook in the red switched-hot wire. Connect it to the bottom brass screw. This half of the receptacle will now only receive power when the wall switch is closed.
- Secure the Device: Carefully fold the wires into the back of the junction box. Keep the ground wires pushed to the very back, followed by the neutrals, then the hots. Mount the receptacle using the provided 6-32 machine screws, ensuring the yoke sits flush against the drywall or plaster ring.
Verify and Test: Expected Multimeter Readings
Do not skip the testing phase. Relying solely on a lamp to test the circuit can hide dangerous wiring faults, such as a bootleg ground or an open neutral. Use a CAT III digital multimeter to verify the exact voltage states before plugging in any sensitive electronics.
| Test Points (Probes) | Switch State | Expected Reading | What it Proves |
|---|---|---|---|
| Top Hot Slot to Ground | N/A | 114V - 126V AC | Always-hot black wire is correctly terminated. |
| Bottom Hot Slot to Ground | OFF | 0V AC | Switched-hot red wire is isolated when switch is open. |
| Bottom Hot Slot to Ground | ON | 114V - 126V AC | Switch loop is complete and brass tab is successfully broken. |
| Top Hot Slot to Neutral Slot | N/A | 114V - 126V AC | Neutral silver tab is intact and return path is solid. |
Reference: For proper multimeter safety and usage techniques, consult the Fluke digital multimeter safety guide.
Switched Outlet Wiring FAQ
Can I wire a switched outlet with only 14/2 or 12/2 cable?
In modern installations, no. Prior to the 2011 National Electrical Code (NEC), electricians often used a 2-wire cable (14/2 or 12/2) as a "switch loop," sending hot down to the switch on the white wire (taped black) and returning the switched hot on the black wire. However, NEC 404.2(C) now requires a grounded neutral conductor to be present at the switch location to accommodate smart switches and timers. Therefore, new switched outlet runs require a 3-wire cable (14/3 or 12/3) to carry the line hot, the neutral, and the switched hot simultaneously. If you are repairing an older home with an existing 2-wire switch loop, you can still wire the receptacle, but you must verify the switch box wiring to identify which wire is the switched return.
Why does my switched outlet have constant power on both halves?
If both the top and bottom receptacles stay on regardless of the wall switch position, you almost certainly forgot to break the brass breakaway tab on the hot side of the receptacle. The tab is bridging the always-hot black wire and the switched-hot red wire, bypassing the switch entirely. Turn off the breaker, pull the receptacle out, and snap the brass tab off with needle-nose pliers. A secondary, less common cause is a miswired wall switch where the line and load wires are tied together under the same screw, or a failed internal switch mechanism.
Does a switched living room outlet need AFCI or GFCI protection?
Under current NEC guidelines, almost all 120V, 15A and 20A receptacles in living rooms, bedrooms, and dens require Arc-Fault Circuit Interrupter (AFCI) protection. This is typically handled at the panel by installing an AFCI circuit breaker, which protects the entire run, including the switched half. Ground-Fault Circuit Interrupter (GFCI) protection is required in wet locations (kitchens, bathrooms, garages, outdoors). Split-wiring a GFCI receptacle for a switched half is highly problematic; you cannot feed the switched hot from the GFCI's "Load" terminals without causing the GFCI to trip or fail to protect downstream devices. If a switched outlet is required in a GFCI zone, the best practice is to use a standard receptacle protected by a GFCI breaker upstream, or use a GFCI receptacle where both halves are unswitched and control the lamp via a smart plug or wireless remote.
