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Real Estate Insight

Home loans

Refinance calculator

Enter your current loan and the new offer. You'll see the monthly saving, when the switching costs are paid back, and what the change costs or saves over the whole loan.

By the Real Estate Insight team · Last reviewed 6 October 2026 · How we check our numbers

Your loan now
$
%
years
$ / year
The new loan
%
years
$

Discharge fee, application and settlement fees, valuation, and the government fees to register the new mortgage and discharge the old one.

$
$ / year

Refinancing $500,000

$235 a month less

$3,517.96 a month now, $3,282.91 on the new loan. The switching costs are paid back in 7 months.

Over the life of the loan

Net switching cost$1,500
Ahead after 5 years$12,603
Total cost staying (25 years)$1,055,389
Total cost switching$986,373
Saved overall$69,016

If you keep paying what you pay now

Put the saving back into the new loan and you'd be debt-free in 21 years, 6 months, paying $150,539 less interest than staying put.

About this estimate. General information, not a loan offer or advice. Monthly principal and interest repayments, rates fixed for the whole term. Check the comparison rate and any break costs if you're on a fixed rate, and whether you'd need to pay lenders mortgage insurance again if you owe more than 80% of the property's value.

Three numbers that decide it

  • The monthly saving, after any difference in annual or package fees.
  • The break-even point: switching costs, less any cashback, divided by the monthly saving.
  • The total cost over the loan, which shows whether a lower repayment is really a cheaper loan or just a longer one.

Keep your old repayment

The biggest win from a lower rate comes from not spending it. If you keep paying what you pay now, the whole saving comes off the principal. On the example in the questions below, that clears the loan years early. The calculator shows how many for your loan.

Before you switch

Check the comparison rate, not just the advertised rate, and ask your current lender to match the offer, which some will do to keep you. If you're on a fixed rate, get the break cost in writing first. And if you owe more than 80% of the value, check whether the new lender would charge lenders mortgage insurance.

Questions people ask

How do I know if refinancing is worth it?
Compare the monthly saving with the cost of switching. If the costs are paid back within a year or two, and you're not planning to sell or refinance again before then, it usually pays. Then check the total cost over the loan, not just the repayment.
How much could I save by refinancing $500,000?
Moving $500,000 with 25 years left from 6.95% to 6.20% cuts the monthly repayment by $235, from $3,517.96 to $3,282.91. With $1,500 of switching costs, that's paid back in 7 months.
Why can a lower repayment cost more?
Because of the term. Refinancing 25 years of debt onto a new 30-year loan lowers the repayment, but you pay interest for five more years. In the example above, a 30-year loan at 6.20% costs $47,055 more in interest than staying on the old loan.
What does it cost to switch home loans?
Usually a discharge fee from your current lender, any application, settlement or valuation fees at the new one, and state government fees to register the new mortgage and discharge the old. Fixed-rate loans can also have break costs, which can be large.
Will I pay lenders mortgage insurance again?
If you owe more than 80% of the property's value, the new lender may charge LMI again, even if you paid it on the first loan. That can wipe out the saving.

Sources