"blueman" wrote in message
...
Can wiring to a light off a 20A circuit be done in 14ga wire?
What about wiring to an upstream 15A receptacle?
Or, does all wiring on a 20A circuit breaker need to be at least 12ga?

Thanks

This depends on the situation. If the box has #12 and your UL listed light
fixture is #14 probably #16 then it is fine.

If your adding the #14 yourself no must be #12.

Open your electric water heater some day, you will have at least #10 feeding
#12.
It is inside a UL listed and labeled appliance, there for ok doky.