"Both companies have consistently scored below average in Consumer's satisfaction surveys since 2010," Ms Chetwin said.
Of the other main players, Mercury Energy and Meridian Energy each scored 70 per cent while Trustpower rated 75 per cent.
Subsidiaries of these companies performed better, Consumer said.
Meridian-owned Powershop scored 94 per cent and Trustpower-owned Energy Direct NZ rated 89 per cent.
Newcomer Flick Electric also rated highly, with 96 per cent of customers who took part in the survey rating the company's performance as "good" or "very good".
Ms Chetwin said overall satisfaction in the industry's performance had dropped since 2012 when ratings reached 78 per cent.
The cost of power is continuing to influence customer satisfaction, she said.
When asked about home heating, 57 per cent of respondents said they could heat their home comfortably but felt they paid too much. A third had cut back on heating because of the cost.
Just 48 per cent thought their retailer delivered value for money.
The survey also found nearly two-thirds of respondents had been cold-called by a power company in the past 12 months inviting them to switch retailer.
However, the majority of respondents who had changed retailer did so as a result their own research, for example by using Consumer's free Powerswitch website.
Almost 8400 Consumer NZ members took part in the survey which was carried out in May 2015.
For more information visit: www.consumer.org.nz.
