Current version of Feeder 18 is: NEC2014.1
Feeder 18 (F-18) consists of two programs: The “Pro” edition and the “Basic” edition.
The “Basic” edition is FREE. (No credit card required). It’s exactly the same as the “Pro” edition except that it is limited to six circuits. Note however that you can access to all of the features of the “Pro” edition.