Withdrawable Balance
NZ$49,000.00
First Home Grant
NZ$5,000.00
Total Available for Home Purchase
NZ$54,000.00
Rates & sources
Standard amortisation formulas used across UK lenders. Interest rates move daily — confirm with your lender or broker.
Source: Bank of England — Statistics — figures refreshed at the start of each tax year.
When to use this calculator
- Before comparing lenders, brokers, or repayment options.
- When you want to test how a different deposit, rate, or term changes affordability.
- When you need a quick estimate before using a formal quote or agreement in principle.
- When you are stress-testing your budget against a potential rate rise to see the impact on monthly payments.
- When you want to understand the full cost of borrowing — not just the monthly figure — before you commit.
A realistic New Zealand planning example
Use these sample inputs as a quick scenario test, then change one variable at a time to compare outcomes.
Total KiwiSaver Balance (NZ$)
NZ$15,000
Years Contributed
25 years
First Home Buyer?
Yes — First Home
After entering these figures, review withdrawable balance, first home grant and total available for home purchase together rather than in isolation — each metric tells a different part of the story. Then rerun the tool with one input adjusted to see which variable has the biggest effect on all three outputs before you settle on a plan.
How to read your results
Withdrawable Balance
Use this metric to compare scenarios side by side and understand how changes in the key inputs drive the final outcome. If the figure surprises you, isolate one variable at a time and rerun the calculation to identify which assumption is responsible.
First Home Grant
Use this metric to compare scenarios side by side and understand how changes in the key inputs drive the final outcome. If the figure surprises you, isolate one variable at a time and rerun the calculation to identify which assumption is responsible.
Total Available for Home Purchase
This is the headline outcome of the calculation, but it is most useful when read alongside the supporting metrics below it rather than in isolation. Try changing one input at a time and watching how this total moves to understand which driver has the biggest impact.
Method & assumptionsAuthoritative sources
This calculator estimates the amount available from a KiwiSaver first home withdrawal and the First Home Grant for eligible buyers. The withdrawable balance is your total KiwiSaver balance minus the $1,000 minimum that must remain in the account. The First Home Grant of $1,000 per year of membership (capped at $5,000 after 5 years) is added if you are a first home buyer with at least 3 years of KiwiSaver membership. Note that the First Home Grant is subject to income caps, property price caps, and other eligibility criteria set by Kāinga Ora — this calculator provides a simplified estimate. Applications for both the withdrawal and the grant should be initiated well before your settlement date to allow for processing time, which can take several weeks. Always discuss your situation with a licensed financial adviser and your KiwiSaver provider before making decisions.
Common mistakes
- !Mixing up loan amount and property value, which can distort affordability and LTV.
- !Using a headline rate but forgetting fees, insurance, taxes, or repayment type.
- !Testing only one term length instead of comparing the payment and total cost together.
- !Forgetting that a repayment mortgage and an interest-only mortgage produce very different monthly figures and total costs.
- !Not accounting for the impact of a rate revert after an introductory fixed period ends, which can sharply increase payments.
What to do next
- Run a second scenario with a higher rate or shorter term so you can see the downside clearly.
- Compare the result with an affordability or overpayment calculator before applying.
- Use the related guides below to understand trade-offs before you request live quotes.
- Note down the monthly payment and total interest for your two or three strongest scenarios so you have a clear comparison ready when you speak to a broker.
- Check whether making a modest overpayment each month would reduce total interest significantly — run the overpayment calculator next to find out.
Frequently asked
Use arrow keys to navigate items, Enter or Space to expand/collapse.
End-of-article next steps
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