Small electricity providers say they're being disadvantaged by unfair tactics from larger competitors to win customers back.
Electricity Authority figures show a record 500,000 power customers switched suppliers last year.
But around 40 percent were enticed back to the original supplier after being offered a better deal.
Electric Kiwi chief executive Luke Blincoe told Nine to Noon that's unfair and should change.
"Only customers that switch are getting benefit of competition and that's not how it should work," he said.
Mr Blincoe said all consumers should feel the benefits of cheaper prices, not just those who want to switch provider.
He suggested the Electricity Authority should impose a 45-day moratorium on power companies which have lost customers trying to win them back.
Outgoing authority chief executive Carl Hansen said there were about 50 electricity providers, making New Zealand one of the most competitive in the world.
But he said an independent advisory group was seeking submissions on whether there was a level playing field.