Wellington power company FreshStart, which has links with Todd Energy, has cut off supply to about 400 homes.
FreshStart general manager Chris Baker said it was unfair to say customers had not had sufficient notice.
"To get on the list they had to have 60 days of debt, so they had had previous warnings already," he said.
Discarded FreshStart customers have a choice of On energy, First Electric, or Contact as their new supplier. But if they have a bad credit history, they are likely to be faced with a bond and prompt payment conditions.
Other power companies said switching people off was a last resort, and several indicated FreshStart's action reflected the price they charged for power.
"If you choose the cheapest option, then you get what you paid for. We have been telling people for months it's worth paying $40 or $50 extra a year to get good service," Trustpower community relations manager Graeme Purches said.
Customers with bad credit or no existing record would have to pay a bond of about $200 before Trustpower took them on, he said.
On energy spokesman Bruce Thompson said the length of time and the number of warnings a customer received before being disconnected related to whether they were a good or bad creditor.
Even a customer with bad credit would receive at least two warnings before being disconnected.
"Disconnecting customers is not a very good way of clearing debt," Mr Thompson said.
Meridian spokesman Alan Seay said cutting off a customer's power was an "extreme step".
Meridian gave nearly two months' notice before disconnection, but would always reconnect customers after payment, he said.
First Electric gave customers 52 days before disconnection.
Meanwhile, the country is continuing to use more than 10 per cent less power than it did at the same time last year.
- NZPA
Feature: Electricity
Energy Efficiency and Conservation Authority
No FreshStart for 400 power bill defaulters
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