Debt-to-income calculator
Your DTI ratio as the Reserve Bank measures it, the most you can owe at a DTI of 6 (owner-occupiers) or 7 (investors), and what counts as debt.
The short answer
With a gross income of $130,000, an owner-occupier’s total debt can be up to $780,000 at a DTI of 6, and an investor’s up to $910,000 at 7. A $700,000 home loan plus $25,000 of other loans and card limits gives a DTI of 5.58.
| Gross income a year | $130,000 |
| Car and personal loans | $15,000 |
| Credit card limits | $10,000 |
| New home loan | $700,000 |
| Total debt | $725,000 |
| DTI: $725,000 divided by $130,000 | 5.58 |
| Most debt at a DTI of 6 | $780,000 |
| Largest new loan at that limit | $755,000 |
| As an investor (DTI of 7) | $885,000 |
At or below 6. You have room for about $55,000 more before the limit, if your income and expenses also pass the bank’s serviceability test.
Debt includes the full limits on credit cards and overdrafts, not the balances. Income is before tax and includes rental income. First Home Loans and new builds are reported to be exempt.
What counts
Kiwibank’s guide sets out how DTI is measured: total debt divided by total gross income.
- Debt: existing home loans, car and personal loans, student loans, the limits of credit cards and overdrafts, and the new loan.
- Income: total yearly income before tax, including salary, rental income and other income.
- Example: $500,000 of debt on an $80,000 income is a DTI of 6.25.
The limits
| Borrower | DTI limit | Allowed above it |
|---|---|---|
| Owner-occupier | above 6 | up to 20% of new lending |
| Investor | above 7 | up to 20% of new lending |
In force since 1 July 2024, and unchanged at the October 2025 and August 2026 reviews. The limits apply across a bank’s lending, not to you personally: a bank can still lend above them for a share of its loans.
interest.co.nz, 14 Aug 2026 · Reserve Bank, 14 Oct 2025 (Scoop)
Exemptions
The Reserve Bank said the main exemptions would be newly built homes and Kāinga Ora loans. Secondary sources also list refinancing, moving a loan and bridging finance. We could not confirm the current wording on rbnz.govt.nz.
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