Leviton 4-Way Switch Wiring Diagram
This is a free printable leviton 4 way switch wiring diagram: download the diagram as SVG or open it and print to paper or PDF.
A 4-way switch wiring diagram shows how to control a light fixture from three or more locations by wiring two 3-way switches at each end of the circuit with one or more 4-way (intermediate) switches in between.
A 4-way switch (called an intermediate switch in IEC/UK terminology) is used in electrical wiring when a light fixture or switched outlet must be controlled from three or more locations. The classic example is a long hallway, a staircase with three or more levels, or a large room with entrances at multiple points.
The circuit architecture always follows the same pattern regardless of the switch brand: a 3-way switch (US) at each end of the circuit, with one or more 4-way switches in the middle. A 3-way switch has three terminals: a common (COM) and two traveller terminals. A 4-way switch has four terminals: two inputs (IN) and two outputs (OUT) — it cross-connects or straight-connects the two traveller wires between consecutive 3-way switches, allowing the circuit state to be toggled from any switch location.
In North American wiring (NEC), the traveller wires between the 3-way and 4-way switches are part of a three-conductor cable (commonly 14/3 or 12/3 Romex, which contains a black, a red, and a white conductor plus a bare ground). The common (COM) terminal on the first 3-way switch connects to the incoming hot (supply) conductor. The traveller terminals connect to the black and red conductors of the three-conductor cable. The 4-way switch receives these two travellers on its IN terminals and outputs them to the next 4-way or the second 3-way switch. The second 3-way switch's travellers connect to its IN terminals; its COM terminal connects to the switched hot wire going to the light fixture.
Leviton is a brand that manufactures 4-way switches to standard configurations. The wiring principle is generic — any compliant 4-way switch from any manufacturer wires identically, because the function is defined by the NEC and by the standard contact configuration. Leviton and similar manufacturers typically mark the four terminals with screws of one colour (e.g. black) on the two IN terminals and another colour (e.g. black with different markings or silk-screen legends) on the two OUT terminals. Always follow the markings on the specific switch and the switch's instruction sheet, rather than relying on assumed colour conventions.
Leviton's residential switch range includes both standard and occupancy/motion-sensing variants, and their 3-way motion switch wiring differs from a conventional 3-way because the sensor switch requires a neutral wire in addition to the line, load, and traveller connections. The companion switch at the other location is usually a standard single-pole or a passive 3-way depending on the model, so always verify the installation guide for your specific Leviton part number before wiring. The free browser-based editor at circuitdiagrammaker.com lets you diagram the full switch leg — including neutral path and traveller routing — before committing to cable.
How to wire leviton 4 way switch wiring diagram
- Plan the circuit and identify the switch locations Determine how many switch locations are needed. Count: first location = 3-way switch (Switch A); each additional intermediate location = one 4-way switch each; last location = 3-way switch (Switch B). Plan the cable runs: use 2-conductor (14/2 or 12/2 with ground) for the supply run to the first switch and the switched feed from the last switch to the fixture; use 3-conductor (14/3 or 12/3 with ground) between all switches in the chain.
- Wire the first 3-way switch (Switch A — supply end) The incoming hot (black) conductor from the supply connects to the COM terminal of Switch A. The black and red traveller conductors of the 14/3 cable running to the next switch connect to the two traveller terminals of Switch A. The bare copper ground connects to the ground screw. The white neutral conductor continues on to the fixture without connecting to Switch A.
- Wire each 4-way switch in the middle Connect the black and red conductors of the 14/3 cable arriving from the previous switch to the IN terminals of the 4-way switch. Connect the black and red conductors of the 14/3 cable leaving toward the next switch to the OUT terminals. Mark the white conductors in each cable with non-white tape at the switch box. Ground the switch to the ground wire.
- Wire the last 3-way switch (Switch B — fixture end) The black and red traveller conductors arriving from the last 4-way switch connect to the two traveller terminals of Switch B. The COM terminal of Switch B connects to the switched hot wire going to the light fixture. Mark the white conductor used as a switched hot with non-white tape. Ground Switch B.
- Wire the light fixture The switched hot from Switch B COM connects to the black (live) terminal of the fixture. The white neutral from the supply (run through all switch boxes but not interrupted) connects to the white neutral terminal of the fixture. The bare ground connects to the fixture ground terminal and the metal enclosure.
- Test the circuit before closing boxes With power applied, verify that the light can be turned on and off from each switch location independently. Toggling any switch must change the light state. If one switch location does not toggle the light, review the 4-way switch IN/OUT terminal wiring at that location.
Specifications
| Standard circuit rating (residential lighting, North America) | 15 A, 120 V (14 AWG copper); 20 A, 120 V (12 AWG copper) |
|---|---|
| 3-way switch terminal count | 3 terminals: 1 common (COM) + 2 traveller (T1, T2) |
| 4-way switch terminal count | 4 terminals: 2 IN traveller + 2 OUT traveller (no common) |
| Cable type for traveller runs | NM-B 14/3 or 12/3 (black, red, white conductors + bare ground) |
| Neutral conductor requirement (NEC 404.2(C)) | Neutral must be available at most switch locations in new construction to facilitate future smart switch installation |
| Re-identification of white traveller conductors | Required per NEC 200.7(C)(1): mark with non-white, non-grey tape at each visible point |
| Governing wiring code (North America) | NEC/NFPA 70; local amendments may apply |
| IEC/UK equivalent switch type | Intermediate switch (4-terminal, 2-pole changeover); used with two-way switches at each end |
Safety warnings
- All residential wiring including multi-way switch circuits must be installed by a licensed electrician with appropriate permits, inspected and approved by the authority having jurisdiction (AHJ), in compliance with NEC/NFPA 70 (USA), BS 7671 (UK), AS/NZS 3000 (Australia/New Zealand), or applicable local codes. This diagram is for educational and reference purposes only.
- Always switch off the circuit breaker at the panel before working on any switch box. Verify that all conductors in the switch box are at zero voltage with a calibrated non-contact or contact voltage tester before touching any wire. In a multi-way switch circuit, multiple cables enter each box and all must be tested.
- In 14/3 or 12/3 cables used in 4-way switch circuits, the white conductor is repurposed as a traveller wire and carries live voltage when the circuit is energised. Mark this conductor at every switch box with non-white tape per NEC 200.7(C)(1). Failure to mark re-identified conductors is a safety hazard for future maintenance personnel who may otherwise assume white means neutral.
- Ensure the switch boxes are not overcrowded (box fill calculated per NEC 314.16). Adding cables to an undersized box causes insulation damage and overheating. If in doubt, use a larger box or a box extender.
- Never use a 4-way switch as a substitute for a 2-way (SPST) or 3-way switch. Wiring a 4-way switch in a simple two-location circuit will not produce correct switching behaviour.
Tools needed
- Calibrated non-contact voltage tester (CAT III)
- Digital multimeter (continuity and voltage)
- Insulated screwdrivers (flat and Phillips)
- Wire strippers
- Needle-nose pliers
- Voltage tester pen or circuit tester
- Electrical tape (including non-white colours for re-identification)
Common mistakes
- Connecting the traveller wires to the COM terminal of a 3-way switch instead of the traveller terminals — this results in the circuit either always on, always off, or not controllable from all locations.
- Swapping the IN and OUT terminal pairs on the 4-way switch — the switch will control the light from two of the three locations but not the third, and the fault is not immediately obvious without understanding 4-way switch operation.
- Failing to re-identify white conductors used as travellers (marking with non-white tape), creating a future hazard for anyone working on the circuit who assumes white is always neutral.
- Using a 14-gauge cable on a 20 A circuit breaker — the breaker rating must match the wire gauge (15 A for 14 AWG, 20 A for 12 AWG).
- Running the neutral through the first switch box without providing it as a conductor in every switch box — the NEC requires a neutral conductor to be available at most switch locations for smart switch compatibility (NEC 404.2(C)).
- Mixing switch brands in a 4-way circuit with different terminal colour conventions and assuming the colours match — always verify with a continuity tester rather than relying on screw colour.
Troubleshooting
- Light does not respond to any switch
- Cause: Circuit breaker tripped, an open circuit in the supply or fixture wiring, or a loose connection at one of the switch COM terminals Fix: Check the circuit breaker. Verify voltage at the first 3-way switch box supply conductor. Verify voltage at the COM terminal of the first 3-way switch. Trace forward through the circuit — check continuity in all traveller wires. Inspect all connections for loose wire connectors.
- Light responds to only two of the three switch locations
- Cause: The 4-way switch traveller pairs are swapped — the IN and OUT pairs are transposed, causing correct operation in one switch position but not the other Fix: With the power off, at the 4-way switch box, swap the two conductors on either the IN terminal pair or the OUT terminal pair (not both). Test. If still incorrect, restore and swap the other pair instead.
- Light flickers or dims when one particular switch is toggled
- Cause: Loose terminal screw on one of the switches creating a high-resistance connection that arcs or fails under load Fix: Identify which switch position causes the flicker. Turn off the breaker. At that switch box, check all terminal screw tightness. A terminal that was hand-tight rather than screw-driver tight will have an intermittent connection. Tighten and test. If arcing damage is visible (blackening), replace the switch.
Frequently asked questions
What is a 4-way switch and when do I need one?
A 4-way switch (intermediate switch in IEC terminology) is used to control a light from three or more locations. Every additional control location beyond two requires one 4-way switch inserted between the two 3-way endpoint switches. For three control points: two 3-way switches and one 4-way. For four control points: two 3-way switches and two 4-way switches.
How does a 4-way switch differ from a 3-way switch?
A 3-way switch has three terminals (one common, two travellers) and connects the common to one of the two travellers. A 4-way switch has four terminals and no common — it cross-connects or straight-connects two pairs of traveller wires. It cannot control a circuit on its own; it only works correctly when installed between two 3-way switches.
Which terminals on a 4-way switch are IN and which are OUT?
4-way switch terminals are typically marked or coloured to distinguish the two input and two output traveller pairs. Some manufacturers use different coloured screws or silk-screen labels. Always consult the wiring instruction sheet supplied with the specific switch. If the switch is not marked, identify the pairs using a continuity tester: in one toggle position, IN1-OUT1 and IN2-OUT2 are connected; in the other, IN1-OUT2 and IN2-OUT1 are connected.
Does the white wire in a 3-wire cable carry live voltage in a 4-way switch circuit?
Yes. In many North American multi-switch wiring configurations, the white conductor in a 14/3 or 12/3 cable is used as a traveller wire and carries live voltage. NEC 200.7(C)(1) requires that such white conductors be permanently identified at each visible location (at every switch box) with electrical tape or paint of a non-white or non-grey colour to indicate they are not neutral. This is a critical safety requirement.
Why does my 4-way switch circuit work from two locations but not the third?
This typically means the 4-way switch is wired incorrectly — specifically, the IN and OUT terminal pairs are crossed, or the traveller wires are swapped at the 4-way switch. As a result, the 4-way switch passes the traveller connection correctly in one position but not the other. Swap one pair of wires at the 4-way switch (swap the connection at either the IN or OUT terminal pair, not both) and test again.
How do I wire a Leviton 3-way motion switch?
Leviton 3-way motion (occupancy sensor) switches require a neutral wire at the sensor location in addition to the standard 3-way traveller and common connections. The sensor unit connects to Line, Neutral, Traveller 1, Traveller 2, and the switched Load or Common depending on the model; the remote switch is typically a standard Leviton companion 3-way switch with no sensor. Always use the specific wiring diagram supplied with your Leviton model number, as terminal labelling and companion switch requirements differ across the product line — particularly between the IPS series and the newer Decora Smart variants.
Related diagrams
- 4 gang 2 way switch wiring diagram
- 4 way intermediate switch wiring diagram
- 4 way light switch diagram
- 4 way switch diagram
- 4 wire 3 way switch diagram
- leviton 3 way switch diagram