NZ Home Affordability Calculator
How much house can you afford? This calculator checks three lending constraints — the RBNZ's DTI ratio, LVR deposit requirements, and bank serviceability — to find your maximum borrowing power.
Key Takeaway
Your maximum borrowing is limited by three constraints: the RBNZ's DTI ratio (6x income for owner-occupiers), LVR requirements (20% deposit), and the bank's serviceability test (repayments under 35% of income at a stress-tested rate). The most restrictive one determines your limit.
Key Facts
DTI Limit
6x / 7x
Owner-occ / Investor
Min Deposit (LVR)
20% / 10% / 35%
Owner / First-home / Investor
Serviceability
35% of income
Max repayment ratio
Stress Test
Rate + 2%
Buffer above current rate
Savings + KiwiSaver withdrawal
Car loans, credit cards, personal loans
Optional — total outstanding balance for DTI calculation
How NZ Home Lending Limits Work
DTI Restrictions (from 1 July 2024)
The Reserve Bank of New Zealand (RBNZ) introduced debt-to-income (DTI) restrictions from 1 July 2024. Owner-occupiers are limited to borrowing 6 times their gross annual income, while investors are limited to 7 times. Banks have a 20% “speed limit” allowing them to exceed these ratios for a small portion of lending.
LVR Restrictions
Loan-to-Value Ratio (LVR) restrictions determine the minimum deposit you need. Owner-occupiers need at least a 20% deposit (80% LVR). First-home buyers may qualify for just a 10% deposit (90% LVR) through the Kāinga Ora First Home Loan. Investors must provide at least a 35% deposit (65% LVR).
Serviceability Testing
Even if you meet DTI and LVR limits, banks will assess whether you can actually afford the repayments. They typically require repayments to be no more than 30–35% of your gross income. Banks also apply a stress test — assessing affordability at roughly 2% above the current interest rate to ensure you can handle rate increases.
First-Home Buyer Advantages
First-home buyers benefit from a lower minimum deposit (10% vs 20%), access to the Kāinga Ora First Home Grant (up to $10,000 per person), and the ability to withdraw KiwiSaver savings toward their deposit. These advantages can significantly increase purchasing power for those entering the property market for the first time.
New Build Exemptions
Newly constructed dwellings are exempt from DTI restrictions. This means if you’re purchasing a new build, the DTI limit does not apply — only LVR and serviceability constraints determine your maximum borrowing. This exemption aims to encourage new housing supply.
Frequently asked questions
What is the DTI (debt-to-income) ratio?
DTI is the ratio of your total debt (including the new mortgage) to your gross annual income. Since 1 July 2024, the RBNZ limits most owner-occupier lending to 6x gross income, and investor lending to 7x. For example, on a $100,000 income you can borrow up to $600,000 (before existing debts are deducted).
What deposit do I need to buy a house in New Zealand?
Most owner-occupiers need at least a 20% deposit (80% LVR). First-home buyers may qualify for just 10% deposit through the Kāinga Ora First Home Loan scheme, though low-equity premiums apply. Investors need a minimum 35% deposit (65% LVR). You can use savings plus KiwiSaver withdrawals toward your deposit.
How do banks assess my ability to repay (serviceability)?
Banks typically require that your mortgage repayments don't exceed 30–35% of your gross income. They also 'stress test' your application at a rate roughly 2% above the current rate to ensure you could still afford repayments if rates rise. This calculator uses 35% of gross income at a +2% stress rate.
What advantages do first-home buyers get?
First-home buyers can access up to 90% LVR (10% deposit) through the Kāinga Ora First Home Loan, can withdraw their KiwiSaver savings (after 3+ years membership), and may qualify for the First Home Grant of up to $10,000 per person. The same DTI limit of 6x applies, but the lower deposit requirement significantly increases buying power.
Can I exceed the DTI limit?
Banks have a 20% 'speed limit' allowing them to exceed DTI restrictions for a limited portion of their lending. This means some borrowers may get approved above the 6x or 7x limit, but it's at the bank's discretion and typically requires strong compensating factors. New build properties are exempt from DTI restrictions entirely.
What about KiwiSaver for my first home?
If you've been a KiwiSaver member for at least 3 years, you can withdraw most of your balance (keeping a minimum of $1,000) toward purchasing your first home. This withdrawal counts toward your deposit. Use our KiwiSaver First Home Calculator to estimate your available withdrawal amount.
Sources
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Last updated April 2026.