You can use 14 AWG wire for a 20 amp lighting circuit. The National Electrical Code (NEC) allows for the use of 14 AWG wire on 20 amp circuits for lighting loads only.The reason you can use smaller wire for lighting loads is because they typically draw less current than other types of loads, such as motors or appliances. Lighting loads are typically inductive loads, which means that they draw a surge of current when they are turned on. However, this surge of current is typically only for a short period of time, and the average current draw of a lighting load is much lower than the surge current.As a result, you can use smaller wire for lighting loads without overloading the circuit. However, it is important to note that you should never use wire that is smaller than the minimum size allowed by the NEC. For 20 amp lighting circuits, the minimum wire size is 14 AWG.Using 14 AWG wire instead of 12 AWG wire can save you money on materials costs. However, it is important to make sure that the wire you use is rated for the ampacity of the circuit. Using wire that is not rated for the ampacity of the circuit can be dangerous and could lead to a fire. Flag for review