Understanding the single-pole switch vs the 3-way North American Switches. Single-Pole Switch vs 3-Way Switch — What’s the Difference? Many wiring mistakes happen because these two switches are confused. Here’s a simple breakdown 👇 Single-Pole Switch Controls one light or circuit from one location Most common switch in homes Has 2 terminals ground Example: Bedroom light controlled from one door 3-Way Switch Controls one light from two different locations Used in staircases, corridors, large roo