What Size Conduit is Needed for 4 or 6 Wires?

This quick reference guide will help you determine what size conduit is needed for 4 or 6 wires.

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If you are running a circuit with 4 or 6 wires, you will need to use a larger conduit than if you were running a circuit with just 2 wires. The following table shows the minimum conduit size that you will need, based on the number of wires in the circuit.

What is a conduit?

A conduit is a tube or pipe used to protect and route electrical wiring in a structure. Conduits can be made of metal, plastic, fiber, or other materials, and are available in various sizes and shapes.

What is the difference between a 4 wire and a 6 wire?

A 4 wire conductor has 4 wires wrapped around a central core. A 6 wire conductor has 6 wires wrapped around a central core. The number of wires in a conductor does not affect the diameter of the conductor.

What size conduit is needed for 4 or 6 wires?

The size of the conduit needed for 4 or 6 wires will depend on the type and size of wire being used. Generally, a larger diameter conduit is needed for 6 wires than for 4 wires.


The table below is a guide for determining the appropriate size (diameter) of conduit needed for a given number of 4 or 6 AWG (American Wire Gauge) copper or aluminum wires. This chart is based on the 2011 NEC (National Electrical Code).

Number of Wires in ConduitQty of WiresSize (Diameter) of ConduitNeeded
4 412″
6 614″