What you meant by local on-net calls?

Answer 1

(OnNet Calls) Phone calls which are made between users of the same network. For example: Calls between Optus mobiles are OnNet, but a call from an Optus mobile to a Vodafone mobile are OffNet. Also called Same Network Calls. simply,On-net means network of one provider.On net number means the number using by the customer of a same service provider.Where customer can call any local on-net number and off-net number

Answer 2

"On-net" generally refers to calls to numbers that are on the same telephone operator's network.