The airline brought back its Covid-19 or sickness flexibility policy to help ease some of the pressure faced by airlines in the first week of the school holidays.
More than 2500 people had swapped their tickets for credit by Monday evening.
But what happens when the airline cancels on you?
A passenger RNZ's Checkpoint programme spoke to was booked to fly Auckland to Christchurch with Jetstar on Saturday until her flight was cancelled.
Jetstar said it would refund her but warned that it could take up to a month for the money to go through.
Needing to get to Christchurch by Monday for an urgent family commitment, Beth decided to book a ticket with Air New Zealand. The one-way ticket cost $400.
"Then, four hours later, I just received a text message saying that flight was also cancelled for operational reasons and it took me to a link," she said.
"It said that I could have one free change, look for another flight for free - but again there were none that would have got me to Christchurch on time - or I could get a credit. So I really didn't have a choice but to accept the credit."
No refund was offered despite Air New Zealand being the one to cancel the flight.
Consumer NZ chief executive Jon Duffy said it was "absolutely not fair" that an airline cancelling a flight refuses to give someone a refund.
"They could be in breach of both the Consumer Guarantees Act and the Civil Aviation Act if the fault is genuinely that of the airline and they're refusing to refund, and in some cases compensate, travellers for the delays."
Duffy said part of the problem was that passengers didn't have clarity from the airlines.
"We think airlines should be doing more to make sure consumers know what their rights are."
When an airline couldn't get a passenger on another flight a refund should be offered, he said.
"We think this is a real failing on the part of the government in this instance because since 2019 the Civil Aviation Act has been in review, has been through a select committee process and the key clause that allows airlines to get away with not refunding consumers ... is still in the legislation."
Air New Zealand declined to be interviewed and could not say how many flights had been cancelled in the past week.
Last week it warned of three-hour waits to get through to its call centre.
While there have been long queues in Auckland today, operations have been running more smoothly at Wellington and Christchurch airports.
Christchurch Airport's chief aeronautical and commercial officer Justin Watson said there had been a few cancellations, caused by weather, engineering issues and "the long tail of Covid-19" which was affecting crews and pilots.
Watson said once flights were cancelled, passengers might have to wait a day or so to get another seat because most flights were full.
"It's an unfortunate situation brought about by Covid and there's not a lot we can do about it when people are getting sick and having to isolate."
Wellington Airport's head of operations Matt Palliser said it had been a busy start to the school holidays with an average of 25,000 travellers per day, the highest numbers since the Covid-19 pandemic began.
"It's great to see everyone travelling again."
Palliser said travellers were being advised to check flight schedules online, check-in online if possible and arrive at the airport early for bag dropoff and to get through security.
Both men said the Ministry of Health has mandated mask use and there was high compliance within the airports and on flights.
"A lot better than you see out in the general public," Watson said.
