The Labour Party has made a pitch to traditional supporters, promising to give low-income earners more tax relief.
Mr Goff used his 'State of the Nation' address in Auckland on Tuesday to unveil more detail of the party's tax policy ahead of this year's election and says if it became government, Labour would make the first few thousand dollars of earnings tax-free.
Mr Goff says a tax-free threshhold - perhaps as high as $5000 - would be proportionately more beneficial to low-income earners.
Removing the tax on the first $5000 of earnings is estimated to cost about $1.3 billion.
But Mr Goff says a Labour-led government would pay for it by cracking down on tax dodgers and an increase for those on high incomes.
Those earning comfortably more than $100,000 a year would be hit by a new top rate of tax, he says.
The party would set up an Anti-Avoidance Tax Task Force to close tax loopholes.
Mr Goff also announced a package to create jobs and raise incomes.
It includes making research and development a priority, building national savings, investing in skills and trade training and changing the way the Reserve Bank works.
Plan fiscally irresponsible - PM
Prime Minister John Key says tax changes proposed by Labour are fiscally irresponsible.
Mr Key says the Government estimates Labour's tax plan will leave it short by $1.1 billion a year if its promise to remove GST from fruit and vegetables is taken into account, and shows a complete lack of understanding of the financial position New Zealand is in.
The money would have to be borrowed and then repaid with interest, and that would leave the country facing a credit downgrade and interest rates would rise, he says.
Revenue Minister Peter Dunne has also dismissed the Labour proposal, saying it was rejected by the former Labour government.
Mr Dunne says the then Finance Minister Michael Cullen rejected the idea because it would have minimal benefit for a small number of low- income earners.
He says a tax-free threshold is even more unsustainable today because the bottom tax rate is lower and there is already more money in the pockets of low-income earners.
