Babies born in 2011 can expect to live to over 90, according to latest life expectancy estimates.
Statistics New Zealand's latest estimate is for a life expectancy of 91.5 years, two years longer than previously projected.
The former estimates, in 2009, were based on trends in longevity dating back to the 1890s.
The latest are based on a shorter historical perspective of 35 years, which Statistics New Zealand says better accounts for improved lifestyles and healthcare.
Waikato University's National Demography Institute emeritus professor Ian Pool says Statistics New Zealand has arguably been too conservative in the past, but says the latest projections are closer to the mark.
The Financial Services Council says the projections underline the need for increased savings to pay for longer retirements.
It says government statisticians the world over have underestimated longevity for the past 30 years and the changes to their working assumptions are long overdue.