Most countries measure their wealth by what they produce. New Zealand measures it by what houses are worth. These are not the same thing, and the gap between them is why our productivity has barely moved in thirty years.
As of early 2026, New Zealand households carry debt equivalent to 90.7% of GDP. Over $370 billion of that sits in residential mortgages alone. That’s not an investment in future productive capacity. It’s hundreds of billions of dollars competing to buy the same existing stock of housing at ever-higher prices. We aren’t building real wealth. We’re repricing it. And we’re doing it deliberately, one tax concession at a time.
The restoration of 100% interest deductibility for rental properties, finalised in April 2025, was the centrepiece of the government’s housing supply strategy. The theory was reasonable enough on paper: reduce holding costs for investors, attract money back into property, generate the pre-sales developers need to break ground, and watch supply follow.
The data from early 2026 suggests the theory has a problem. Total building work fell 3.1% in the December 2025 quarter, with residential building specifically down 1.1%. Consents for multi-unit dwellings have edged up in a few areas, but nothing resembling a supply response has arrived.
This is predictable, not surprising. Tax perks for buyers don’t lower the cost of timber, concrete, or skilled labour. What they do is prop up a price floor on land. When the government de-risks land ownership through tax subsidies, it creates an incentive to hold land rather than build on it. The two things look similar. They’re not.
MBIE’s own construction pipeline data projects infrastructure spending to rise to $19.6 billion by 2030, yet the residential sector continues to grind under persistent construction cost pressures and a skills shortage that no tax break can resolve. Investors operating rationally respond to the incentives in front of them: acquire land, hold, wait for appreciation. The building itself is almost incidental to the strategy.
That’s not a criticism of investors. It’s a criticism of a system that has made land banking more profitable than building.
In New Zealand’s main centres, land now accounts for roughly 65–70% of a property’s total capital value. That single figure tells you most of what you need to know about what’s gone wrong.
When a local council uses ratepayer money to put in a new busway, upgrade a park, or improve local roads, the value of nearby land goes up. The landowner — who has contributed nothing beyond holding a title — pockets 100% of that gain as private profit. The community funded the improvement. The landholder collected the dividend.
Economists have a name for this: the “unearned increment.” It’s a polite phrase for something that should make people uncomfortable.
A Land Value Tax addresses this directly. Unlike a general property tax that falls on buildings and improvements, a land value tax is levied only on the unimproved value of the land itself. The logic is straightforward: land cannot be hidden, moved, or parked in an overseas structure to reduce a tax bill. As a result, it’s one of the most efficient tax bases that exists — the harder you make land banking, the more land gets used productively.
The practical effect matters in a way that tax breaks for landlords simply don’t. When land itself carries an ongoing tax obligation, holding empty sections or underused lots in high-growth areas becomes expensive. The owner either builds to generate income to cover the tax or sells to someone who will. Profit stops attaching to ownership and starts attaching to use.
This isn’t a fringe position. Support for land value taxation runs across the ideological spectrum — from right-leaning economists who want to shift the burden away from taxing productive work and investment, to those on the left who see it as the most direct tool for addressing inherited wealth. Henry George made the argument in the 1870s. The idea hasn’t disappeared because nobody has countered it. It’s stayed marginal because the people who would pay it tend to have more political influence than those who would benefit.
There’s a bigger problem sitting underneath the housing debate that rarely gets addressed directly.
Why do so many New Zealanders with spare capital choose a second investment property over backing a local business, putting money into an NZX-listed company, or investing in the equipment and systems that actually drive productivity? Because the system has deliberately de-risked land speculation. Between interest deductibility, capital gains that are largely tax-free for long-held properties, and the psychological security of an asset you can see and touch, residential property has been set up as the obvious choice.
The consequence runs through the entire economy.
Treasury’s long-term fiscal analysis has warned that government debt could approach 200% of GDP by 2065 if current trends hold. We cannot fix a trajectory like that while hundreds of billions in capital cycles through existing housing rather than flowing toward the businesses, technologies, and infrastructure that generate new productive output.
Treasury’s own research on capital intensity confirms what business owners have long understood: New Zealand’s productivity has stagnated not because our people are lazy or untalented, but because they’re working with insufficient tools, thin capital bases, and limited access to the investment that raises real wages over time.
A house built in the 1970s provides the same shelter today that it did then. It doesn’t generate exports, doesn’t drive wages up, and doesn’t create anything new. When we treat it as an investment vehicle rather than as a piece of infrastructure, we price out the people who need it for shelter and tie up enormous amounts of capital that could be used for something genuinely productive elsewhere.
The objection you’ll hear most often is that property investment underpins rental supply, and without investors, renters would have nowhere to live.
There’s a real concern buried in that argument. It just doesn’t survive contact with the economics.
People need shelter. That demand doesn’t disappear if the speculative premium in land prices fades. If land were taxed at its productive value, land prices would stabilise, and the incentive to build would still exist — because people still need places to live. Developers would compete on the quality and cost-efficiency of what they build, rather than on who can lock up the best sites first.
Housing would still be built. It would just be built to house people, not to generate returns from appreciation.
New Zealand has long been described as a property market with a country attached. It’s a sharp line because it’s accurate.
We’ve incentivised the least productive part of our economy for forty years. A generation has been priced out of home ownership. Businesses struggle to compete for capital against the returns that land appreciation has historically provided. And Treasury is already warning about the fiscal consequences of staying on this path.
The reforms required — land value taxation, honest treatment of capital gains, and breaking the link between government revenue and ever-rising land prices — are politically difficult because too many voters currently benefit from the arrangement as it stands. They know it, the parties know it, and so the conversation keeps getting deferred.
That’s not a reason to avoid the argument. It’s the reason to make it clear and keep making it.
Steve Baron is a New Zealand-based political commentator and author. He holds a BA with a double major in Economics and Political Science from the University of Waikato and an Honours Degree in Political Science from Victoria University of Wellington. A former businessman in the advertising industry, he founded the political lobby group Better Democracy NZ. https://stevebaron.co.nz
Jack says:
The 90.7% household debt to GDP ratio is wild when you think about it. How much of that mortgage pile is actually funding productive assets versus just bidding up existing house prices?
Isabel Cruz says:
The 90.7% figure does raise serious questions about capital efficiency. You’ve identified the core issue: how much of that debt is actually creating economic value versus simply inflating asset prices. If most of it’s the latter, we’re funding consumption through equity extraction rather than building productive capacity. That’s a structural problem that doesn’t resolve itself.
callum_vid says:
That 90.7% figure is mental. The thing that’s been bugging me is how much of it’s genuinely locked into productive stuff versus just chasing the same finite pool of houses. You’d reckon if all that borrowing was actually building new productive capacity, we’d see different economic outputs by now. But from what I can see, a fair chunk of it just cycles between existing properties getting revalued. Makes you wonder what the actual multiplier effect is when most