"There may be thousands of our customers dealing with Omicron in the coming weeks, and we want them to know they don't need to worry about their flights."
It is a return to the fare flexibility scheme which was launched in reaction to the original Covid outbreak, and which expired in October last year.
The airline introduced flexi and flexi-refund fares with insurance against disruption, last year. Flexible fares will still be available during this period, says the airline.
Many passengers hold fares they no longer wish to use after summer events being cancelled, with respect to the omicron outbreak.
However, the airline has also predicted that an increased number of people being required to isolate may impact the plans of both travellers and air crew.
There could be further disruption ahead.
Last weekend an Air New Zealand crew member tested positive for omicron, resulting in 15 colleagues being stood down. There were six flights registered as places of interest on the Covid-19 contact tracing list.
Customers who changed their flights between 24 January and 27 January should call the Air New Zealand contact centre on 0800 737 000 to arrange a refund on change fees.