New Zealand: six times for owners, seven for investors
New Zealand caps total debt against gross income rather than measuring the payment as a share of income, which is an unusual shape and worth getting straight. The Reserve Bank's debt-to-income restrictions, in force since 1 July 2024, allow six times income for owner-occupiers and seven times for investors. What is being tested is the size of the debt, not what it costs you each month, so a lower interest rate does not buy you a larger loan under this rule.
Each limit comes with a speed limit rather than a hard stop: no more than 20% of a bank's new lending in each category may exceed its multiple. Individual borrowers do get written above the caps, but the allowance is scarce and banks ration it.
The restrictions sit alongside the loan-to-value rules, which govern the deposit. The two bind on different things, one on how much you owe relative to income, the other on how much you owe relative to the property, and an application has to satisfy both, plus the bank's own affordability assessment on top.
Because the New Zealand rule caps the loan rather than the ratio, the percentages on this page are a guide to how stretched you are, not a test you can pass. The maximum borrowing figure is the one to plan around, and your existing debts will still reduce what a bank offers inside it.