A Green Government would hike the tax rate to 40 per cent on income over $140,000 and use the extra revenue to tackle child poverty.
The party's $1 billion poverty package includes new tax credits for low-income families and children in their first few weeks of life. These would be extended to the children of students and beneficiaries.
The party has this afternoon launched its election campaign in Auckland and also announced plans to harmonise the trust tax rate with the top income tax rate and crack down on avoidance. Its costings say this would generate and extra $1bn a year.
Under the plans, the Family Tax Credit and the In-work Tax Credit would be scrapped and replaced with a Children's Credit, worth an extra $60-a-week. It would be extended to those who currently miss out on the In Work credit, which is available only to parents who work more than 20-30 hours a week.
The Greens say this will benefit an extra 130,000-150,000, to the tune of $3000 a year.
Newborns from the poorest families will also get an extra $2,200 in the first ten weeks of life. The Greens' Parental Tax Credit (at $220 a week) will go to 13,000 babies whose parents don't get paid parental leave.
An extra $500m year will also be invested in health and education for children
Co-leader Metiria Turei said the policies were aimed at "building a fairer society where every child in this country has enough of what they need to thrive." Every cent of the extra tax revenue would go towards poverty alleviation.
There are 205,000 children living in poverty costing taxpayers $6-8billion a year, she said.
"Kiwi kids growing up in poverty are three times more likely to be admitted to hospital, five times more likely to die of cot death, and 27 times more likely to get rheumatic fever, and die earlier than those who are better off."
The Greens are aiming for a 15 per cent share of the party vote in September's election, boosting their caucus from 14 to 20 MPs.
The polls consistently place the party at 11-12 per cent, but they have struggled to gain traction as the media focus on tussles between other minor parties.
However, insiders say campaign managers refuse to be distracted from their core messages. The campaign is built around policy launches in three key "priority" areas: kids, clean rivers and an innovative economy.
"Friends and colleagues, in 34 days time, we can make history, by becoming the first ever Green Party in Government in Aotearoa," Turei told supporters this afternoon.
"We have lead the opposition for the last three years and we are ready to lead in Government."
National's associate finance spokesman Steven Joyce said the tax hike would penalise school principals, doctors, and many small business owners and stall economic recovery.
"And it is of course just another in a long list of new taxes Labour and the Greens want to introduce including a capital gains tax, a big carbon tax, taxes on water use, higher personal taxes, and regional fuel taxes," he added.
By the numbers
3 per cent - of taxpayers affected by the Greens new top income tax rate of 40 percent on every dollar earned above $140,000
$500m - the extra revenue raised every year from their new tax rate
$620 million - raised from hiking the trust tax rate to 40 percent and limited tax avoidance through trusts
$60 - a week extra in a Childrens Credit, which would extend the In-Work TAx credit to parents currently ineligible
$2,200 - in a Parental Tax Credit over ten weeks for new born babies whose parents don't get Paid Parental Leave.
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