Mortgage Refinance Calculator
Compare staying with your current home loan against refinancing. See your repayment change, switching-cost break-even point and whether extending the loan term could cost you more over time.
Compare your mortgage
Enter your current loan and a refinance offer. Example values are shown as placeholders only.
Switching costs & cashback
Your refinance comparison
Enter your mortgage details to compare repayments, financing costs and the point where switching costs are recovered.
| Comparison | Current loan | Refinance |
|---|---|---|
| Loan term | ||
| Remaining interest | ||
| Lifetime fees | ||
| Total financing cost |
Why refinancing needs more than a repayment comparison
A lower interest rate can reduce repayments, but switching costs, annual fees and extending the loan term can change the real result. CalcNest separates monthly cash flow from financing cost so a longer mortgage does not automatically appear to be a saving.
We track interest and fees month by month to estimate when the refinance moves ahead after upfront costs and cashback.
Resetting a mortgage to a longer term may lower repayments while increasing the amount of interest paid over the life of the loan.
Keeping your existing remaining term is the default comparison so you can see the effect of the new rate without quietly adding years to the mortgage.
How refinancing a mortgage works in Australia
Refinancing replaces your existing home loan with a new loan, either with your current lender or another lender. A lower rate can reduce interest, but the useful comparison is the new loan's total cost after switching expenses, ongoing fees and any change to the remaining term.
Before switching, ask whether your existing lender can improve your rate or loan package. A better retention offer can avoid some of the costs and paperwork of changing lenders.
Include discharge or break costs, application and establishment charges, valuation or settlement costs, possible LMI and ongoing package fees. Treat cashback as a benefit, not as proof the loan is cheaper.
If you have 18 years left and refinance into a fresh 30-year loan, your required repayment may fall because the debt is spread over another 12 years. That can increase total interest even with a lower rate.
How to compare a refinance properly
Start with the mortgage you actually have today, then compare the new offer on the same remaining term before considering a longer reset term. That separates the benefit of the lower rate from the effect of simply taking longer to repay the debt.
Enter the balance, rate, remaining years and months, annual fees and the average balance you normally keep in offset.
Use the offered rate and fees, then include the real costs of leaving the old lender and establishing the new loan.
This is the cleanest way to see whether the new pricing itself saves money. Then test a custom term if changing the repayment timeline is part of your plan.
A lower monthly repayment is only one result. Check when switching costs are recovered and whether the refinance stays ahead through the life of the loan.
Refinancing costs to include
Actual charges depend on the lender, loan and property. Use the calculator's switching-cost fields for costs that apply to your situation rather than assuming refinancing is free.
Possible discharge or termination charges and, for some fixed-rate loans, break costs. Check the payout figure from your lender before relying on an estimate.
Possible application, establishment, valuation, legal or settlement charges. If your equity is limited, lender's mortgage insurance may also affect the economics of switching.
Compare annual or package fees as well as the headline interest rate. Features such as an offset account can be valuable, but only when the benefit is worth any extra rate or fee.
When refinancing may — or may not — make sense
The new rate and fees create a persistent financing-cost saving, switching costs are recovered in a reasonable period and the loan features still suit how you manage your mortgage.
The repayment falls mainly because the term is longer, the break-even point is far away, a cashback hides higher ongoing costs, or you would lose a useful offset/redraw feature.
Do not assume today's entered rate will last forever. Consider how repayments would fit your budget if rates, income or living costs change.
More CalcNest mortgage tools
Estimate principal-and-interest repayments and total mortgage cost.
Mortgage Offset CalculatorSee how an offset balance may reduce interest and change your payoff timeline.
Australian Home Buying CostsEstimate the upfront costs involved when purchasing a property in Australia.
Mortgage refinancing FAQs
The rate matters, but so do switching costs, loan term, equity and the features you are giving up or gaining.
How much lower should my new rate be before refinancing?
There is no single rate gap that makes refinancing worthwhile for everyone. The useful test is whether the estimated interest and fee savings recover your switching costs and remain ahead over the period you expect to keep the loan.
Should I refinance back to a 30-year term?
A new 30-year term can reduce the required monthly repayment, but it may also keep you in debt much longer. Compare the same remaining term first, then use the longer-term scenario to understand the cash-flow benefit and additional lifetime cost.
Does an offset account change the refinance comparison?
Yes. Money held in a 100% offset can reduce the balance used to calculate interest. Compare the average offset balance and any package or account fees on both loans rather than looking at the headline rate alone.
How should I treat refinance cashback?
Enter cashback as a reduction in the net upfront switching cost, but still compare the ongoing rate, fees and loan term. A cashback offer can improve early break-even without necessarily making the loan cheaper over the long run.
What is the break-even point when refinancing?
It is the point where estimated financing-cost savings recover the net upfront cost of switching. This calculator models the loans month by month rather than simply dividing switching costs by a repayment reduction.
Can a refinance save money at first but cost more later?
Yes. A longer new loan term can reduce repayments and create early savings, but keeping the debt for additional years may eventually make the refinance more expensive. CalcNest checks for this reverse crossover.
Should I reset my mortgage to 30 years?
A longer term can improve monthly cash flow, but it may materially increase lifetime interest. Compare the same remaining term first, then consider whether lower required repayments are worth the additional borrowing cost.
Does this calculator use current lender rates?
No. Enter the rate you want to test. Results are estimates and do not represent an available loan, approval or lending quote.
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