How Much Can I Borrow as a First Home Buyer in New Zealand
One of the biggest questions first home buyers ask is: "How much can I actually borrow?" It is a fair question, and the answer depends on a few things — your income, your expenses, your deposit, and which bank you apply with. Every lender does the maths a little differently, so two banks can give you two different answers for the exact same situation.
This guide breaks it all down in plain English so you know what to expect before you even sit down with a mortgage adviser.
What Do Banks Look At?
When you apply for a home loan, the bank wants to know one thing: can you comfortably afford the repayments? To figure that out, they look at your income, your living expenses, any debts you already have (like credit cards, car loans, or buy-now-pay-later), and how much deposit you have saved.
They also stress-test your application. That means they do not use the actual interest rate you will pay — they use a higher test rate (usually around 8% to 9%) to make sure you could still afford repayments if rates went up. This is why you might feel like you can afford more than the bank says — they are being cautious on purpose.
How Does Income Affect My Borrowing Power?
Your income is the starting point. If you are on a salary or wages, banks will generally use 100% of your gross income. If you earn overtime, bonuses, or commission, most banks will only count 80% of that — and they usually want to see a consistent history before they include it.
If you are self-employed, banks typically need two years of financial accounts prepared by an accountant. They will look at your net profit and may add back things like depreciation and interest payments to get a clearer picture of your actual earnings.
For joint applications, both incomes are combined — which is one reason buying as a couple or with a family member can increase your borrowing power significantly.
What About My Expenses and Debts?
Banks do not just look at what comes in — they also look at what goes out. Your regular living expenses (groceries, power, phone, transport, insurance) are all factored in. Most banks use a combination of what you declare and their own benchmarks based on household size.
Existing debts have a big impact. Credit cards are assessed on the full limit, not just what you owe. So if you have a $5,000 credit card limit, the bank assumes a monthly repayment of $150 to $190 even if you pay it off every month. Buy-now-pay-later accounts like Afterpay work the same way. Closing unused credit cards and BNPL accounts before you apply can make a real difference to how much you can borrow.
How Much Deposit Do I Need?
Most banks require a minimum 20% deposit to avoid paying a low equity margin (an extra fee on top of your interest rate). However, first home buyers can often borrow with as little as 5% deposit through schemes like the Kainga Ora First Home Loan.
Your deposit can come from your own savings, KiwiSaver first-home withdrawal, or a non-repayable gift from a family member. The more deposit you have, the more you can borrow — and the better your interest rate options.
What Is the Debt-to-Income Ratio?
Since July 2024, all New Zealand banks must follow debt-to-income (DTI) limits set by the Reserve Bank. For owner-occupied homes, your total debt cannot be more than six times your annual gross income. For investment properties, the limit is seven times.
For example, if you earn $80,000 a year, your maximum total debt (including the new mortgage) would be $480,000 under the DTI rules. This is a hard cap that applies on top of the bank's own affordability calculations.
Why Do Different Banks Give Different Answers?
Each bank has its own way of calculating affordability. Some use a net income approach, others use gross income with different scaling. They also have different minimum surplus requirements — ANZ needs just $1 per month surplus, ASB needs $120 per month, and Westpac needs $150 per month. These differences mean one bank might approve you for $50,000 more than another.
This is exactly why working with a mortgage adviser matters. An adviser can run your numbers across multiple banks and find the one that gives you the best result for your specific situation.
A Simple Example
Let us say you and your partner earn a combined $120,000 per year before tax. You have $60,000 saved for a deposit (including KiwiSaver), no credit cards, and modest living expenses. Under DTI rules, your maximum debt would be $720,000. Depending on which bank you go with and their affordability calculations, you might be approved for a home loan somewhere between $550,000 and $650,000 — giving you a purchase price range of roughly $610,000 to $710,000 with your deposit included.
But change one thing — say you have a $10,000 credit card limit — and that borrowing power drops. Every detail matters.
How Can I Increase My Borrowing Power?
There are a few practical steps you can take before applying. Pay off or close any credit cards and buy-now-pay-later accounts you do not need. Reduce your personal loans or car finance if possible. Make sure your income documentation is up to date — recent payslips, employer letter, and if you are self-employed, current financial statements. Save as much deposit as you can, and check whether you are eligible to withdraw your KiwiSaver for your first home.
Talk to NiuLIFE Home Loans
At NiuLIFE Home Loans, we help first home buyers across New Zealand understand exactly how much they can borrow — and which bank is the best fit. We run your numbers across all the major lenders so you get the full picture, not just one bank's answer. Whether you are just starting to save or ready to make an offer, we are here to walk you through every step in plain English. Get in touch for a free no-obligation chat.