A recent comparison of Air New Zealand flights found some prices have increased by nearly 300 percent.
But the airline has accused the comparison of being "quite misleading".
Consumer New Zealand said it compared 11 Air NZ flights in 2023 and 2024 and compared the costs to equivalent flights between 2019 and 2021.
All flights, except one, were more expensive - with prices rising between 34 and 297 percent.
Consumer NZ communications and campaigns advisor Abby Damen said the "steep increase" was hard for Kiwis already struggling with domestic flights - given the limitations of how many are available.
"It's not great news if the only travel option you have is to fly. It's no surprise that New Zealand consumers are questioning how and why flight prices have increased so much over the past few years."
Consumer NZ found a return flight from Wellington to Hamilton for two adults with no luggage, booked two days in advance, would have cost $281.20 in 2021 - but now would cost $1118. Consumer NZ said this was an increase of 297 percent.
It also found a flight for a family of four from Sydney to Palmerston North in March 2020 would cost $1372.
Now, it would cost $3451.
"A Christchurch-Dunedin return trip booked with 5 weeks lead-in time cost $123.60 in 2020. The same flight in 2023 cost $344 - nearly three times as much," Damen said.
"A return trip between Wellington and Dunedin for two people and one checked bag cost $487.20 in 2020. Fast-forward to 2024 and the price of the flights had effectively doubled to $970."
Damen said the organisation regularly received complains from Kiwis frustrated about not only the cost of flying, but cancellations as well.
"If you travel to or from the regions, like Gisborne or Whangārei, your options might be to grin and bear it - or not fly at all."
Damen said Kiwis relied heavily on Air New Zealand as the national carrier.
"Depending on where you live, an Air New Zealand flight may be your only choice," she said.
Air New Zealand's head of domestic Scott Carr said it was "really disappointing" to see such comparisons made - and "quite misleading".
"If you take 2021, we're in the middle of a pandemic, we have closed international borders, we're trying to restart our business, we're trying to fill our empty flights, we're trying to get people travelling again."
Carr said people may have been able to find cheap fares during that time but it was not a fair comparison - and sampling just 11 flights was not a fair sample size.
"We carry 11 million people around our domestic network every year," he told Morning Report.
Carr admitted fares were up - but so were Air New Zealand's costs - an increase of 42 percent.
"Our average fares across our domestic network are only up 22% - so it's highly misleading."
Damen said there were many genuine reasons for the increase in airfares but the significance in some meant the industry needed to be monitored closely.
Carr said there was "plenty of talk" about a market study and it was not fair to single out airfares as the sole issue.
He said Stats NZ reviewed its airfares every month and released its own data.
Challenged on Stats NZ not having the same access as Air New Zealand would to its information, Carr said: "Our fares are completely transparent. You can go onto our website and see our fares. We're not hiding anything; customers can see the fares."
ISSUE
