Wiring a switched outlet—commonly known as a half-hot or split-wired receptacle—allows one half of a standard duplex outlet to be controlled by a wall switch while the other half remains continuously powered. This is the standard configuration for living room lamp control. The direct answer to how this is achieved is simple: you use a standard 15A or 20A duplex receptacle, run a 3-conductor cable (like 14/3 NM-B) between the switch and the outlet, and physically break the connecting brass fin on the hot side of the receptacle to isolate the two halves.

This guide provides the exact device ratings, wire gauges, and termination steps required to execute this safely and to code, eliminating the guesswork around which cable to pull and which fin to snap.

The Decision Path: Which Switched Outlet Configuration Do You Need?

Before pulling wire, you must determine the exact switching logic your space requires. Use this decision table to select the correct configuration and the specific hardware needed for the job.

Scenario Configuration Cable Required Concrete Hardware Pick
Lamp Control
(Living room/bedroom; one half switched, one half always hot)		 Half-Hot / Split Receptacle 14/3 NM-B (15A) or 12/3 NM-B (20A) Leviton 5262 (15A Duplex) + Leviton 1451 Switch
Appliance Control
(Garbage disposal; entire outlet switched on/off)		 Fully Switched Receptacle 14/2 NM-B (15A) or 12/2 NM-B (20A) Standard Duplex (fin intact) + 15A/20A Toggle Switch
Smart Home Integration
(Voice/schedule control without rewiring the outlet)		 Smart Plug / Always Hot Standard 14/2 NM-B or 12/2 NM-B Lutron Caseta Smart Plug (No outlet rewiring needed)

Default Recommendation: For standard residential living spaces where a wall switch controls a floor lamp, select the Half-Hot configuration using a Leviton 5262 (15A) receptacle and 14/3 NM-B cable. This satisfies NEC requirements for lighting control while preserving an always-hot socket for electronics or vacuum cleaners.

Tools, Materials, and Device Ratings

Using the correct wire gauge and device rating is non-negotiable. A 15A circuit requires 14 AWG copper and a 15A breaker; a 20A circuit requires 12 AWG copper and a 20A breaker. Never put a 20A receptacle on a 15A breaker, and never use 14 AWG wire on a 20A breaker.

Materials List

  • Receptacle: 15A/125V duplex receptacle (e.g., Leviton 5262 or Eaton 1877). Must be a standard duplex, not a GFCI (GFCIs cannot be split-wired on the load side).
  • Switch: 15A single-pole toggle switch (e.g., Leviton 1451).
  • Cable: 14/3 NM-B (Romex) with ground if on a 15A circuit. The three conductors are Black, Red, and White, plus a bare copper ground.
  • Wire Nuts/Connectors: Yellow or red twist-on wire connectors, or Wago 221 series lever nuts (preferred for solid copper).
  • Pigtails: 6-inch lengths of 14 AWG THHN (black, white, green) for grounding and neutral splices.

Tool List

  • Non-contact voltage tester (NCVT) (e.g., Klein NCVT-2)
  • Digital multimeter (capable of measuring AC voltage and continuity)
  • Wire strippers (capable of stripping 14 and 12 AWG solid wire)
  • Needle-nose pliers (for breaking the receptacle fin)
  • Phillips and flat-head screwdrivers

Mains Safety: De-Energize and Verify

WARNING: LETHAL VOLTAGE

Working inside an electrical box exposes you to 120V AC, which can cause fatal electrocution or severe arc flash. You must completely de-energize the circuit before removing any cover plates.

  1. Turn off the circuit breaker supplying the switch and outlet at the main panel.
  2. Place a piece of tape over the breaker to prevent accidental re-engagement (Lockout/Tagout).
  3. Test the outlet and switch with a Non-Contact Voltage Tester (NCVT).
  4. Verify dead with a multimeter: Set your multimeter to AC Volts. Measure from the hot slot (shorter slot) to the neutral slot (longer slot), and from hot to the ground hole. Both readings must be exactly 0.0V.

Disclaimer: This guide provides NEC-style guidance for educational purposes. Your local Authority Having Jurisdiction (AHJ) has final authority, and local code may require a licensed electrician for this work.

Step-by-Step: Wiring the Half-Hot Switched Outlet

The following steps assume the most common and code-compliant routing: Line power enters the switch box first, and a 14/3 NM-B cable runs from the switch box to the outlet box. Modern NEC code (since 2011) requires a neutral wire at the switch location for future smart-switch compatibility, which is why we use 14/3 cable instead of 14/2 for the switch loop.

Part 1: Preparing the Receptacle

  1. Take your 15A duplex receptacle (Leviton 5262) and locate the two brass screws on the hot side.
  2. Between these two brass screws is a small metal connecting tab (fin).
  3. Using your needle-nose pliers, grip the brass fin and bend it back and forth until it snaps off completely. Do not touch the silver fin on the neutral side.
  4. Verify the break: The top brass screw and bottom brass screw must now have no physical metal connection between them. The two silver screws must still be connected by their intact fin.

Part 2: Terminating the Switch Box

  1. Grounding: Twist the bare copper ground wire from the incoming line cable together with the bare copper ground wire from the 14/3 outgoing cable and a 6-inch green/bare pigtail. Secure with a wire nut. Connect the other end of the pigtail to the green ground screw on the switch.
  2. Neutral Splice: Twist the white wire from the incoming line cable together with the white wire from the 14/3 outgoing cable. Secure with a wire nut. Note: The switch itself does not terminate the neutral, but the neutral must pass through the box to satisfy modern code.
  3. Line Hot: Connect the black wire from the incoming line power to the bottom brass screw on the single-pole switch.
  4. Switched Hot: Connect the red wire from the 14/3 outgoing cable to the top brass screw on the single-pole switch. (The black wire of the 14/3 cable will carry the always-hot power, which we will handle in the next section).
Pro-Tip: J-Hooks

When terminating wires to screw terminals, strip exactly 3/4 inch of insulation. Form a "J-hook" with the wire using your needle-nose pliers. Loop the hook clockwise around the screw so that tightening the screw pulls the loop tighter, rather than pushing it out.

Part 3: Terminating the Outlet Box

  1. Grounding: Connect the bare copper ground wire from the 14/3 cable to the green ground screw on the receptacle.
  2. Neutral: Connect the white wire from the 14/3 cable to one of the silver screws on the receptacle. Because the silver fin is intact, this single connection provides a neutral return path for both the top and bottom halves of the outlet.
  3. Always-Hot (Top Half): Connect the black wire from the 14/3 cable to the top brass screw on the receptacle. This half will now have continuous power.
  4. Switched-Hot (Bottom Half): Connect the red wire from the 14/3 cable to the bottom brass screw on the receptacle. This half will now be controlled by the wall switch.

Verify and Test: Expected Meter Readings

Do not plug in expensive electronics until you have verified the wiring with a multimeter. Turn the breaker back on at the panel and keep the wall switch in the "OFF" position.

  1. Set Multimeter: Set to AC Voltage (V~), auto-ranging or 200V scale.
  2. Test Top Half (Always Hot): Insert probes into the top receptacle (Hot to Neutral). Expected Reading: 120V (Acceptable ANSI C84.1 range is 114V to 126V).
  3. Test Bottom Half (Switched OFF): Insert probes into the bottom receptacle (Hot to Neutral). Expected Reading: 0.0V (or a harmless ghost voltage of 1-3V which will drop to 0 under load).
  4. Test Bottom Half (Switched ON): Flip the wall switch to "ON". Test the bottom receptacle again. Expected Reading: 120V.
  5. Neutral-to-Ground Check: Measure from the neutral slot to the ground hole on both halves. Expected Reading: < 1.0V (ideally < 0.5V). A reading higher than 2V indicates a loose neutral connection or shared-neutral overload.

The Most Common Botch (and How to Fix It)

The single most frequent mistake when wiring a switched outlet is forgetting to break the brass fin, or accidentally breaking the silver fin.

Symptom 1: Both halves turn on and off with the switch.

  • The Cause: You forgot to snap the brass fin. The always-hot black wire and the switched-hot red wire are feeding into the same continuous brass bus bar. Because the switch controls the red wire, the entire bus bar is being backfed through the switch loop when the switch is on, or the always-hot is overriding the switch, keeping both on.
  • The Fix: Turn off the breaker, remove the outlet, and snap the brass fin.

Symptom 2: The breaker trips immediately, or the bottom half simply doesn't work.

  • The Cause: You accidentally snapped the silver (neutral) fin. If the silver fin is broken, the bottom half of the outlet has no neutral return path back to the panel. If you mistakenly wired two separate neutrals to the now-isolated silver screws, you have created an illegal and potentially dangerous Multi-Wire Branch Circuit (MWBC) violation that can overload the neutral conductor and cause a fire.
  • The Fix: Discard the receptacle. A broken neutral fin compromises the structural integrity of the device. Buy a new Leviton 5262 and only break the brass fin.

By strictly following the 14/3 NM-B routing, isolating the hot side via the brass fin, and verifying your 120V readings at the receptacle slots, you will achieve a reliable, code-compliant half-hot outlet that handles daily lamp switching without failure.