The government's $12 million influenza vaccination expansion campaign kicks off today, with wider eligibility for free doses and a 40 percent increase in supply.
Free vaccines supplied by the government become available today.
Eligibility is expanding to include Māori and Pacific people 55 years and older, estimated to be 39,000 people.
Other people covered includes people aged over 65, pregnant, or with underlying conditions. Employers often also pay to supply flu vaccines to staff.
Health Minister Andrew Little said the number of doses was increasing to 2 million this year, up from about 1.4 million.
He said only about half of those eligible usually took up the flu vaccine, but the virus kills more than 500 people a year in New Zealand, and he urged everyone - especially the most vulnerable - to take it up.
Doctors have been warning this flu season could be particularly bad in New Zealand, with less exposure due to Covid-19 lockdowns meaning a lower level of immunity over the past two years.
With Covid-19 continuing to spread in New Zealand, lower levels of immunity against the flu and other winter illnesses could mean further heightened pressure on the health system.
"We're looking at ways to increase the vaccination workforce to get flu shots to those who need them," Little said.
"With the Omicron wave still working its way through the country, we need to protect our most vulnerable from getting the flu as well, and our health system from coming under more pressure."
The typical New Zealand flu season is around June to August.
The $12 million for expanding the influenza vaccination programme is being funded through the Covid-19 Response and Recovery fund.