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Mortgage Calculators

Use our mortgage calculators to make smarter decisions that save you money in the long-run. Work out how much you can borrow for a mortgage or use the mortgage repayment calculator to figure out what home loan repayments you'd be looking at and whether or not you should refinance your mortgage.

Calculate how much cash you could save

Try out our refinance calculator to see if you could save on interest or get cash immediately by refinancing to a new bank.

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How Lenders assess your affordability

Lenders test your ability to afford a mortgage by looking at your repayments over a 30-year term, based on a test mortgage rate of around 9.00%.

Lenders will include 100% of your PAYE income, or the average of the past two year's business income if you're self-employed. For investment properties, lenders will include a maximum of 80% of the rental income. For owner-occupied properties, lenders have varying boarder income policies, however you can typically count on up to two boarders at $200 each per week — just keep in mind that this will be dependent on each lender's unique policy.

The other big factor when it comes to affordability is disclosure of expenses, which get assessed on a more granular level. Even if you're careful with your spending, lenders will still set a baseline living cost for each person, so be ready for that when they crunch the numbers.

Lenders are looking for affordability to be evident in account conduct and bank behaviour. For a first home buyer, the amount you save plus your rent plus discretionary expenses is a good indication of how much you can afford.

Tips to increase how much you can borrow

Generally avoid having consumer finance debt, but regardless, reduce your credit card limits. Lenders will apply a monthly amount of 4% of your limit to your expenses. So if you have a $30,000 credit card limit, that will have an implied monthly expense of $1,200.

That might not make sense given that it is probably interest-free. But if your income is over the repayment threshold set by the government, 12% of every dollar you earn over the threshold goes towards paying off your student loan. These repayments can have a massive impact on servicing. For example, if you earn $120,000 per year, your repayments will be $1,000 per month which reduces your borrowing power by around $100,000. You can find out what the repayment threshold is here, and run some numbers with IRD's student loan repayment calculator here.

Keen for the best rate and some cash too?

We've teamed up with award winning mortgage experts, Squirrel.

With over 1,425 five star reviews on Shopper Approved, Squirrel has helped thousands of Kiwis just like you secure the best possible rate when refixing or refinancing.

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New Zealand

five star revews

Our experience with Squirrel has been fantastic. Our Advisor was friendly and professional and made what can be a stressful and complex process very seamless for us. We are thrilled with our outcome.



New Zealand

five star revews

Helped me get an improved rate and sorted out my needs. Great communication, kept me up to date throughout the process.

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