Raising the retirement age and introducing a capital gains tax are among the OECD's recommendations for reforming the economy.
The Paris-based organisation's report on the country highlights low national savings and the associated high level of international debt.
While the current account deficit has shrunk, it's expected to widen again
as the recovery takes hold and the private sector starts to spend again, the report says.
"With markets focusing closely on sovereign and national indebtedness, such a scenario is riskier than it was."
Returning to fiscal surpluses should be a priority, and the Government should aim for a larger medium-term surplus than the 2 per cent of GDP foreshadowed in the December economic and fiscal update.
The OECD recommends raising the qualifying age for NZ Super and ceasing indexing it to the average wage.
It also suggests removing KiwiSaver subsidies to higher-income savers, most likely to have shifted their savings form other sources.
It attributes New Zealand's lower living standards, relative to Australia and the OECD average, to poor labour productivity from low business investment and capital intensity per worker.
A comprehensive capital gains tax, excluding the family home, would reduce the bias towards housing investment.
State-owned enterprises perform better than those in many countries, but would be improved by full, or even partial, privatisation.
The report approves of the emissions trading scheme, but says the price signal should be strengthened by auctioning permits to industry rather than the current free allocation.
