Data from the Electricity Authority show 69,000 account holders switched energy companies from March through August this year.
The rate of switching was particularly pronounced over the winter months, with the rates of defection increasing significantly in May, June and July.
Each of these months saw large increases when compared to the movement of customers a year earlier.
The winter data this year corresponds with a period of increased working from home, as the nation grappled with the Government's lockdown response to the coronavirus pandemic.
The big winners from the exodus of customers were smaller players Electric Kiwi with a gain of 13,100 customers and Nova Energy, which added 8900 to its customer roster.
Electric Kiwi chief marketing officer Andrew Cooper says that movement of customers indicates that Kiwis are on the hunt for deals in a tough economic climate.
"Unfortunately there is a very large number of New Zealanders who have never switched and many of these people will be paying too much," Cooper says.
"We would encourage those people to have a look around to see if there is a better deal out there. A great place to start is Consumer NZ's Powerswitch website."
Cooper says it is particularly rewarding for a smaller firm like Electric Kiwi to win the tussle for customers, given his company simply doesn't have the big budgets of the major companies.
"At Electric Kiwi we like to do things ourselves: we built our own tech in-house, all of our service is in-house, and we even make our own ads," he says.
"The recent Electric Kiwi song ad was actually a little jingle, written by me, for our Christmas party. At the end of the first lockdown I was trying to figure out what would connect with Kiwis at such a strange time, and in the end I just thought that the song would be fun.
"It's a little cringey, but it's real and we are making fun of ourselves a little bit which I think is okay. That ad was shot on a tiny budget by myself and my head of creative Lance McMinn and all of the actors are staff members and their families."
This stripped back approach appears to hitting the mark in the battle for cut-through against bigger players.
While major power company Meridian added 7500 customers, the same could not be said of the other major players in the market.
Mercury saw its customer numbers drop by 13,500, Genesis by 11,300 and Contact by 9700.
Mercury GM of retail digital Kevin Angland attributed the drop in customers to heightened competition in the market but added that the company is shifting its focus to loyalty and customer value rather than overall numbers.
"This focus has led to us reducing activity to gain new customers and, as a result, our overall customer numbers have gone down," Angland said.
"During this period our customer advocacy, measured by our net promoter score, and customer satisfaction measures have held up strongly."
The switching data does, however, only tell part of the story for some energy companies. Contact general manager of profitable growth Matt Bolton explained that this data does not account for the customers his firm added through its acquisition of Energy Club.
"We have approximately 4,000 more electricity connections than we did at the end of February 2020," Bolton said.
The contact executive further explained that the company now has close to 35,000 broadband connections on the book, which have been acquired through its promotion of bundle packages.
The Herald also contacted Genesis for comment on the data.
Despite the movement of tens of thousands of Kiwis, New Zealand's energy hierarchy remains in place when it comes to overall customer numbers.
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With 496,000 customers at 31 August, Genesis Energy remains the most popular provider by some stretch.
This is followed by Contact Energy on 417,000, Mercury on 346,000, Meridian on 328,000 and Trustpower on 264,000.
The contingent of smaller players is led by Nova Energy on 111,000 customers, followed by the Pulse Energy Alliance on 78,000 and Electric Kiwi on 65,000.
Vocus and Flick Electric sit further back on 34,000 and 23,000, respectively.
While the smaller players are making incremental gains, there is still a long way to go for any of these to challenge the market clout of bigger, more established providers.