Hawke's Bay people overpaid for power by more than $8 million last year, according to the Electricity Authority.
A new report on the performance of the residential electricity market in 2015 showed people in Hawke's Bay could have saved $8,854,618 or $135 per household last year by switching to the cheapest deal available.
Hastings Budget Advisory Service co-ordinator Kristal Leach said a lot of clients came to the service with electricity issues at this time of year.
"They often have high power arrears and they might have a disconnection notice."
A disconnection would damage their credit history and make it difficult to find a supplier. It was best for clients on lower incomes or benefits to pre-pay for electricity, because it gave them control over the amount they spent.
Budget advisers could call power providers for help around getting on to a pre-paid plan, which meant clients would pay slightly more for power in summer, but wouldn't experience the winter price spike.
Leach said people should come to the budgeting service for help with power bills sooner rather than later.
"If client can't afford their power one week, they need to come and see us that week and then we can ring the company and let them know and see if we can get a better arrangement in place for them."
Leach said a lot of clients used limited power and were eligible for low user charges, so it could be economic for them to switch providers to get the cheapest deal.