How can I wire a switch into an extension cord?
Improper Electrical Wiring constitutes a serious life safety hazard. It can be the source of structural fire and potentially fatal shocks.

I am not saying that you can't splice a common electrical wall switch into an extension cord. I am saying that it is not a good general practice.

Consider Instead


Installing a suitable hardwired outlet and wall mounted switch using techniques suited for permanent installation in the structure.
Alternatively, consider using a listed extension chord with an integral switch such as this or that.