Property and Mortgage

New Build vs Existing Home: The Money Comparison

🏗️ Two very different purchases

Buying a brand-new build and buying an established home are two very different financial decisions, even when the asking prices look similar. A new build is bought either as a fixed-price turnkey package or under a build contract with progress payments, its price already includes GST, and it usually comes with a builder guarantee and lower maintenance in the early years. An existing home comes with mature gardens, established chattels and room to negotiate, but it can carry deferred maintenance and older insulation. The differences run deeper than the sticker price. New builds are treated more favourably under the Reserve Bank lending rules, they are exempt from both the loan-to-value ratio (LVR) and the debt-to-income (DTI) restrictions, which can let you buy with a smaller deposit. This guide walks you through the purchase mechanics, the finance and tax rules that actually apply in 2026, and four worked New Zealand examples so you can compare the true cost of ownership rather than just the price on the listing.

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                Key Point: A new build and an existing home at the same price are not the same deal. New builds are exempt from the Reserve Bank LVR and DTI restrictions, their price already includes GST, and they carry a builder guarantee. Existing homes offer established gardens, chattels and negotiating room, but budget for maintenance and possible insulation upgrades.
            

What counts as a "new build"?

For tax purposes a new build generally means a self-contained dwelling that received its code compliance certificate (CCC) on or after 27 March 2020. For lending, a bank usually treats a home as a new build if it is recently completed and bought from the developer within about six months of its CCC, or you are buying off the plans or building it yourself. The key point is that a bank treats finance for a new build differently from finance for an established home, and so do some of the tax rules.

Two ways to buy a new build

Method	How you pay	Who carries the build risk
Turnkey (fixed price)	A deposit on signing (often 10%), then the balance on completion when you get the keys and the CCC	The developer, until handover
Build contract (progress payments)	You settle the land, then draw down the loan in stages as each part of the build is finished	You, from the land settlement onward

💡 GST is already in the price

When you buy a new home from a developer, the price you are quoted already includes GST. The developer accounts for the GST to Inland Revenue, so you do not add 15% on top and you cannot claim it back for a private home. A private sale of an existing home between two people who are not GST-registered has no GST at all. This is why a new build price and an existing home price are not directly comparable.

New build strengths

Builder guarantee: A registered builder can offer a Master Build Guarantee or a Registered Master Builders guarantee covering defects and, in some cases, non-completion
Lower early maintenance: New materials, new appliances and a build to the current Building Code, so little to spend in the first years
Warmer and drier: Built to current insulation and ventilation standards rather than a 1970s standard
Favourable finance: Exempt from the Reserve Bank LVR and DTI restrictions

New build trade-offs

Delays and variations: A build can run late, and variations to the contract can push the final price above the original quote
Smaller sections: New subdivisions often have compact sections and less established landscaping
Progress-payment interest: Under a build contract you pay interest on drawdowns during construction, often while still paying rent

Existing home strengths and trade-offs

Established and negotiable: Mature gardens, existing chattels, a known street, and a price you can often negotiate
Renovation upside: Room to add value over time
Maintenance and insulation: Budget for repairs, and possibly for insulation, heating or wiring upgrades on an older home

💰 The purchase mechanics and running costs

The way you pay, and what you pay for after settlement, differs sharply between a new build and an existing home. Understanding both sides helps you compare the true cost of ownership rather than just the purchase price.

Turnkey versus build contract cash flow

With a turnkey (fixed-price) purchase you pay a deposit on signing and nothing more until the home is finished. You keep renting while it is built, and your mortgage interest only starts when you settle on completion. The price is locked, so you carry no build-cost risk, but you also have less say over changes once the contract is signed.

With a build contract you settle the land first and then draw down the loan in stages as the foundation, framing, roof, lining and fit-out are completed. You pay interest on the growing drawn balance during the build, and you may still be paying rent elsewhere. The upside is more control over the design and, sometimes, a lower total price.

⚠️ Watch for variations and delays

A build contract quote is only fixed for the work described. Variations, such as a change of finish or a site issue like difficult ground, can add cost. Delays extend the period you are paying both interest on drawdowns and rent on your current home. Build a contingency of at least 5% to 10% into your budget, and check whether your contract is truly fixed price or a "cost plus" arrangement.

The deposit

On an existing home you generally want a 20% deposit to avoid a low-equity premium, although banks can still lend above 80% for a limited share of their new lending. On a new build the Reserve Bank exemption gives banks more room to lend with a small deposit, and the Kainga Ora First Home Loan allows a deposit as low as 5%. We cover the finance rules in detail in the next section.

Guarantees on a new build

A Master Build Guarantee (offered through Registered Master Builders) is an optional guarantee a builder can arrange that covers loss of deposit, non-completion and defects for a set period after the build. It is not automatic, so confirm in writing which guarantee applies and what it covers. A 10-year structural guarantee is common. An existing home has no equivalent, which is why a pre-purchase building inspection matters so much when you buy established.

Maintenance over time

Cost area	New build (first 5 years)	Existing home (first 5 years)
Structural repairs	Low, often covered by guarantee	Variable, roof, piles or cladding can be costly
Painting and weatherproofing	None expected	Exterior repaint may be due
Insulation and heating	Meets current standards	May need topping up or a heat pump
Appliances and fittings	New, under warranty	May need replacing

💡 Section size and rates

New subdivisions often come with smaller sections, which can mean lower council rates and less garden to maintain, but also less land value growth over the long run. Established homes usually sit on larger sections with mature planting, which many buyers value but which cost more to maintain. Weigh both the ongoing cost and the lifestyle you want.

📊 Finance and tax: where new builds are treated differently

The biggest money difference between a new build and an existing home is not the price, it is how the Reserve Bank lending rules and the tax rules treat each one. Here is the current position for 2026, verified against the Reserve Bank and Inland Revenue.

Loan-to-value ratio (LVR) restrictions

The Reserve Bank limits how much high-LVR lending banks can do. From 1 December 2025 the settings are:

Owner-occupiers: banks can write up to 25% of their new owner-occupier lending at an LVR above 80% (that is, to buyers with less than a 20% deposit)
Investors: banks can write up to 10% of their new investor lending at an LVR above 70% (less than a 30% deposit)

                New-build LVR exemption: Loans to build a new home, or to buy a newly built home from the developer within 6 months of the code compliance certificate, are exempt from the LVR restrictions. That gives banks far more freedom to lend above 80% on a new build without using up their limited high-LVR quota.
            

Debt-to-income (DTI) restrictions

DTI restrictions have applied since 1 July 2024 and cap lending to borrowers who are already heavily geared relative to income. The current settings are:

Owner-occupiers: banks can write up to 20% of new owner-occupier lending at a DTI above 6 (that is, total debt more than 6 times gross income)
Investors: banks can write up to 20% of new investor lending at a DTI above 7

                New-build DTI exemption: Building a new home, or buying a newly built home from the developer, is exempt from the DTI restrictions. An extension to an existing house is not exempt. Combined with the LVR exemption, this can make a new build easier to finance than an existing home of the same price.
            

The Kainga Ora First Home Loan

The First Home Loan is underwritten by Kainga Ora and issued by participating banks and lenders. It lets eligible first home buyers borrow with a deposit as low as 5%, rather than the usual 20%. To qualify your gross income over the last 12 months must be:

$95,000 or less for a single buyer with no dependants
$150,000 or less for a single buyer with one or more dependants
$150,000 or less combined for two or more buyers, regardless of dependants

There are no house price caps on the First Home Loan, so you can buy at any price provided you meet the income caps and your lender is satisfied you can service the loan. It works for both new builds and existing homes, and it pairs naturally with the new-build LVR exemption.

⚠️ The First Home Grant no longer exists

The First Home Grant, which once paid up to $10,000 for a new build or $5,000 for an existing home, closed to new applications on 22 May 2024 as part of Budget 2024. Do not budget for it. The First Home Loan and the KiwiSaver first home withdrawal remain available, but there is no longer a cash grant tied to whether you buy new or existing.

The bright-line test now applies equally

For any residential property sold on or after 1 July 2024, the bright-line test is 2 years for every type of property. If you sell within 2 years of buying, any gain is taxable unless an exclusion, such as the main-home exclusion, applies. If you sell after 2 years, the bright-line test does not apply.

⚠️ Ignore the old "5 years for new builds, 10 years for existing" rule

Before 1 July 2024, new builds had a shorter 5-year bright-line clock while other homes had a 10-year clock. That distinction has been removed. From 1 July 2024 the period is a flat 2 years for new builds and existing homes alike, so the bright-line test is no longer a reason to prefer one over the other. The old rules can still matter for a property bought and sold before that date.

🔢 Four worked New Zealand examples

These examples use illustrative interest rates and cost estimates to show how the comparison works. Your own figures will differ, so treat them as a method rather than a quote.

Aroha and Sam: $700k new build vs $750k existing

Situation: Aroha and Sam are choosing between a $700,000 new build and a $750,000 established home. To compare running costs fairly, assume both buy with a 20% deposit and a 6.0% illustrative interest rate.

Deposit and loan:

New build deposit: $700,000 × 20% = $140,000, so the loan is $560,000

Existing home deposit: $750,000 × 20% = $150,000, so the loan is $600,000

The existing home needs $10,000 more deposit

First-year interest (illustrative 6.0%):

New build: $560,000 × 6.0% = $33,600

Existing home: $600,000 × 6.0% = $36,000

The existing home costs $2,400 more interest in year one

Maintenance over the first 5 years:

New build: about $1,000 per year = $5,000, much covered by guarantee

Existing home: about $5,000 per year = $25,000 (repaint, roof, insulation top-up)

Existing home also pays a pre-purchase building inspection of about $800

Five-year maintenance gap: $25,000 - $5,000 = $20,000 in the new build's favour

                    What it shows: The new build is cheaper to buy and cheaper to run in the early years. The established home costs more upfront and in maintenance, but offers a mature section and existing chattels. The right choice depends on how much you value those against the extra cost.
                

Priya: a small deposit and the new-build exemption

Situation: Priya has saved $80,000 and is looking at a $600,000 property. She wants to know whether buying new makes her deposit stretch further.

Buying an existing home:

A 20% deposit would be $600,000 × 20% = $120,000

Priya's deposit: $80,000 ÷ $600,000 = 13.3%

She needs the bank to lend above 80%, which it can only do for up to 25% of its new owner-occupier lending, so approval is not guaranteed

Buying a new build:

New-build lending is exempt from the LVR restrictions, so the bank is not using its limited high-LVR quota

The First Home Loan allows a 5% deposit: $600,000 × 5% = $30,000

Priya's $80,000 (13.3%) is well above the 5% minimum

Her loan would be $600,000 - $80,000 = $520,000, and approval is easier because the exemption applies

💡 Why the exemption matters

The same $80,000 deposit gives Priya a much clearer path to finance on a new build than on an existing home, because the new build sits outside both the LVR and DTI limits. If she is a first home buyer within the income caps, the First Home Loan strengthens that further.

The Nguyen family: turnkey vs build contract

Situation: The Nguyens can buy a $750,000 turnkey home, or buy a $350,000 section and build a $400,000 house under a build contract, for the same $750,000 end value. Assume a 6.0% illustrative rate and a 9-month build.

Turnkey (fixed price):

Deposit on signing: $750,000 × 10% = $75,000

Balance on completion: $675,000

No construction-period interest, they keep renting until handover

Build contract (progress payments):

Land settles first, so $350,000 is drawn from day one

Interest on the land for 9 months: $350,000 × 6.0% × 9/12 = $15,750

Build drawdowns average about $200,000 across the build

Interest on drawdowns: $200,000 × 6.0% × 9/12 = $9,000

Construction-period interest: $15,750 + $9,000 = $24,750, plus rent while building

⚠️ Progress payments cost cash flow

The build contract exposes the Nguyens to roughly $24,750 of interest during the build, on top of any rent, before they even move in. The turnkey option defers that cost and locks the price, but gives them less control over the design. A build contract can still work out cheaper overall or give a better home, as long as they budget for the carrying cost and a contingency for variations.

Tama: the bright-line test applies to both

Situation: Tama has heard that new builds have a shorter bright-line period, and is weighing a new build against an existing home he might sell within a few years.

The current rule:

For property sold on or after 1 July 2024, the bright-line test is 2 years for both new builds and existing homes

If the property is his main home, the bright-line test generally does not apply at all

The old 5-year (new build) versus 10-year (existing) split no longer exists

If he buys a rental and sells within 2 years:

Buys an existing rental for $750,000, sells 18 months later for $820,000

Taxable gain: $820,000 - $750,000 = $70,000

Tax at his 33% marginal rate: $70,000 × 33% = $23,100

A new build sold in the same window would be taxed the same way

💡 Bright-line is no longer a tie-breaker

Because the 2-year period is identical for new builds and existing homes, the bright-line test should not sway Tama's choice. Decide on price, finance, running costs and the home itself. If you may sell within 2 years, factor in the possible tax, and check the main-home exclusion with a tax adviser.

Related tools and guides

📚 Sources

Verified July 2026 against: Reserve Bank of New Zealand, loan-to-value ratio restrictions and the 1 December 2025 settings; Reserve Bank of New Zealand, debt-to-income restrictions (in force from 1 July 2024); Inland Revenue, the bright-line test for property sold on or after 1 July 2024; and Kainga Ora, First Home Loan eligibility. The First Home Grant closure on 22 May 2024 was confirmed via Budget 2024.

🎯 Test Your Knowledge

Complete this 10-question quiz to check your understanding of new builds versus existing homes

1. For residential property sold on or after 1 July 2024, how long is the bright-line test period?

2 years

5 years for new builds and 10 years for existing homes

10 years for all property

No bright-line test applies

2. How are new builds treated under the Reserve Bank loan-to-value ratio (LVR) restrictions?

They are exempt from LVR restrictions

They need a higher deposit than existing homes

They must always have a 20% deposit

LVR rules do not exist in New Zealand

3. Is GST added on top of the price when you buy a brand-new home from a developer?

Yes, you add 15% GST to the purchase price

No, the price a developer quotes already includes GST

Yes, but only on the land portion

GST is refunded to the buyer after settlement

4. What is the minimum deposit under the Kainga Ora First Home Loan?

20%

10%

5. What happened to the First Home Grant?

It was doubled to $20,000 in 2024

It closed to new applications on 22 May 2024

It now applies only to existing homes

It was replaced by a stamp duty

6. In a fixed-price turnkey new build, when do you usually pay the balance?

In monthly instalments during construction

On completion, when the home is finished and you get the keys

Before the foundation is poured

Only after you sell your old home

7. What is a common downside of a build contract with progress payments?

You pay interest on drawdowns during the build, often while still paying rent

The price can never change

You cannot get a mortgage

GST is charged twice

8. Which guarantee commonly covers defects on a new build by a registered builder?

The bright-line guarantee

The Master Build Guarantee

The LVR guarantee

The KiwiSaver guarantee

9. Which is typically true of an established home compared with a new build?

It always has better insulation

It usually comes with mature gardens and established chattels

It never needs maintenance

It is exempt from the bright-line test

10. How are new builds treated under the Reserve Bank debt-to-income (DTI) rules?

They are exempt from DTI restrictions

They face a lower DTI limit than existing homes

DTI rules apply only to new builds

New builds must have a DTI under 3

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