Winter is coming, so the Electricity Authority (EA) is urging people to think about their power bills.
Its website -- whatsmynumber.org.nz -- allows people to shop around for a good deal.
Chief executive Carl Hansen says: "There are more electricity options than ever before, with a record number of retailers in the market, so it is worth shopping around."
Last year 419,000 customers switched companies. That compares with 388,000 in 2011.
The EA says nearly two million consumers have switched providers since 2011, when the "What's My Number" campaign began.
The estimated average saving for people who switched in 2014 was $162.
Mr Hansen says price is not the only thing people should think about.
Here are three other important factors.
The EA says some retailers offer different rates depending on how much power you use and at what time of the day you use most of that electricity.
It is possible to request data from your supplier on your usage for the past 24 months. You can show that data to other potential suppliers when they are offering you a deal.
You can also use the data to look at ways of reducing how much power you use, or to look at switching to solar or gas.
The Authority says if you have a smart meter you will have more options when it comes to choosing a plan.
If you are unsure about whether you have a smart meter, your provider can tell you. They can also let you know what is involved to have one installed.
Having a smart meter means you do not have to deal with 'estimated' bills and there is no need for a meter reader to enter your property.
The EA says most plans are monthly, but you can also ask for a weekly bill or go on a prepay plan.