Western Bay power bills jumped by nearly $140 in the last year and some consumers are having to cut down on expenses such as fuel as a result.
Business, Innovation and Employment Ministry survey figures show average household power costs increased $139 in the 12 months to February in Tauranga.
Nationally, average power bills were up $121.
The survey compared electricity prices available to new customers on February 15 to rates offered on the same day last year.
Local Energy Online customers experienced the biggest hike ($178). Part of this was due to a $75 increase in Powerco lines charges.
Meanwhile, TrustPower, which has about 60,000 Western Bay customers, lifted its price to $113.15 for Tauranga customers, while 600 Otago customers enjoyed a $104 drop. They were with the Network Waitaki lines company.
TrustPower spokesman Graeme Purches said the increase was "well below the average" and a 20 per cent increase in transmission charges justified it: "That is charged to the network company Powerco, which passes those charges on to us along with its network [local line] charges.
Overall, the network charge from Powerco went up by 10.7 per cent."
Transmission and network charges accounted for about 38 per cent of a standard bill.
"In that environment, a total increase of 6 per cent to consumers was, I believe, very reasonable and certainly a lot less than some of our competitors," Mr Purches said.
The next price review for Tauranga and the Western Bay of Plenty was expected from May 1 and this year's increase was expected to be 3 per cent - for a typical customer 16 cents per day, or $58.40 per year.
Mr Purches said the Otago drop reflected the small number of customers on the Waitaki network, mostly farmers. The servicing cost for those customers was lower than Tauranga's because of "economies of scale".
"Over 70 per cent of consumers are with us, which is reflected in the comparative size of our increase last year."
Tauranga mum Casey Fredericks said the hike would hurt many families and especially the elderly.
"My biggest thing is where is the money going to come from out of the budget?
"There's only so much wrapping up in blankets you can do. There's going to be a lot more poverty, disconnections and hospitals will be overrun because people will get cold and sick."
Tauranga Budget Advisory Service co-ordinator Diane Bruin advised paying weekly instalments for power:
"People are reducing usage of vehicles and riding bikes instead, to minimise expenditure."
New Zealand's Electricity Authority said competition between power retailers was key in keeping prices down.
In the past four years, four independent retailers had entered the market, with four others considering it, chief executive Carl Hansen said.
Consumer NZ recommended customers "shop around" to ensure they got the cheapest rates.