"This may reflect the pressures of work and family responsibilities as people move through middle life," principal statistician Paul Brown said.
"If you think of the young adults, the thing there is the world is their oyster. There's that thing about being fresh and young and not having the burdens of life yet. Life's a party.
"And at the older end perhaps the traditional notion of what retirement is - the time when you can let it all go and enjoy those Autumn years."
Money - particularly a lack of it - had a major impact on people's feelings of well-being.
Life satisfaction dropped to 77 per cent for people living in households with an annual income under $30,000, and jumped to 86 per cent for those in the $30,001-$70,000 bracket.
The next group of $70,001-$100,000 had a smaller increase to 89 per cent satisfaction, and 92 per cent of those in a household with an annual income of more than $100,000 were satisfied.
"That's quite intuitive that when you're on a low income, any increment in your income is going to make quite a big difference," Mr Brown said. "But as you go up the income scale the incremental effect becomes less and less. So it's like a diminishing return."
The findings closely match those of the first survey, done in 2008.
New Zealanders' overall life satisfaction is above the OECD average and comparable that in Australia and the United Kingdom.
However, while overall life satisfaction was high, 48 per cent of New Zealanders reported they had "not enough" or "just enough" money for necessities such as accommodation and food.
More than a third of those surveyed said there was an issue such as dampness, size and heating in the house or flat in which they lived.
One-third said they felt unsafe walking alone in their neighbourhood at night, and 25 per cent felt they did not have enough contact with family members they did not live with.
Unemployed people were the least satisfied of all marked population groups, 30 per cent reporting being dissatisfied or neither satisfied nor dissatisfied.
Nearly half of those unemployed felt they were too poor to meet everyday needs and were also more likely to report feeling socially isolated.
Other groups with below-average satisfaction included people living in one-parent family households, renters, and those without educational qualifications.
Factors with little bearing on overall life satisfaction included gender, what region of New Zealand people live in, whether people were born in New Zealand, and ethnicity.
The General Social Survey 2010 was answered by 8550 people between April 2010 and March 2011.
