How much house can I afford?

It comes down to two things: your deposit and the mortgage repayment you can comfortably manage. This calculator turns the repayment you can afford into a loan amount at a given rate and term, then adds your deposit to estimate the house price you can reach.

What deposit do I need in New Zealand?

Most banks want at least a 20% deposit, though some lending is available with less, often at a higher rate. A larger deposit reduces the loan, the repayments, and usually the interest rate offered.

What repayment can I afford?

A common guide is to keep housing costs under about a third of your take home pay, but the right figure is what fits your budget with room for rates, insurance, and rising interest. Banks also test your loan at a higher rate than the current one.

House Affordability Calculator

This calculator works out the house price you could realistically afford in New Zealand, starting from the two numbers that actually matter: your deposit and the mortgage repayment you can comfortably manage each month. Rather than guessing a price and hoping the numbers work, it flips the usual approach around. You enter your deposit, the monthly repayment you are confident you can sustain, the interest rate, and the loan term in years. The calculator reverses the standard mortgage formula to find the largest loan that repayment would service, and adds your deposit on top to give the house price you could reach. It also returns your deposit as a percentage of the price, which lenders use as the loan to value ratio and which affects both approval and the interest rate on offer. Use it before you start house hunting or approach a bank or broker, so you search in a realistic price range rather than falling for a home that stretches your budget too far. It is also handy for testing how a bigger deposit, a longer term, or a change in interest rates shifts what you can afford. Remember that banks assess your full income, debts and living costs, and test affordability at a higher rate than the one on offer today, so treat the result as a starting guide rather than a guaranteed lending figure.

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Deposit

Repayment you can afford (monthly)

Interest rate

Term (years)

house price you could afford

Maximum loan$0

Deposit as % of price0%

A guide only. Banks test your loan at a higher rate and assess your full income and outgoings.

How it works

The calculator reverses the mortgage formula. From the repayment you can afford, the rate, and the term, it finds the largest loan that repayment would service. Adding your deposit gives the house price you could reach. It also shows your deposit as a share of the price, which lenders look at as the loan to value ratio.

Worked example

With a $120,000 deposit and $3,000 a month at 6.5% over 30 years, the repayment supports a loan of about $475,000. Added to the deposit, that is a house price near $595,000, with the deposit about 20% of the price.

Related calculators

Borrowing Capacity Calculator: how much a bank may lend.
Mortgage Repayment Calculator: repayments on a loan.
House Deposit Savings Calculator: save your deposit.
First Home Buyer Calculator: first home costs.

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