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Compare weekly, fortnightly and monthly repayments side by side — and see exactly how much interest and time you could save by changing your payment schedule.
Most borrowers set their repayments to monthly and never revisit the decision. But switching to fortnightly or weekly can save tens of thousands in interest and cut years off your loan — simply by changing when you pay, not how much.
Get in touch with The Kapital and we'll walk through the numbers with you.
Talk to a broker →Australian banks calculate mortgage interest daily — your balance is multiplied by the daily rate every single day. The sooner you reduce that balance, the less interest accrues. Paying more frequently means your balance drops before as much interest can accumulate.
This calculator uses the accelerated method, which is how most Australian lenders apply fortnightly and weekly repayments:
The key insight is that there are 26 fortnights in a year — not 24. So paying half your monthly amount 26 times adds up to 13 monthly payments in a year instead of 12. That one extra monthly payment each year reduces your principal faster in every subsequent period, compounding the savings over the life of the loan.
On a $750,000 loan at 6.14% over 30 years, the difference between monthly and fortnightly is roughly one extra payment of around $4,600 per year. Each of those dollars reduces your outstanding balance — so the interest calculated on that balance the following day is lower. Over 30 years, small differences in the outstanding balance compound significantly.
In practice, the difference between accelerated fortnightly and accelerated weekly is small. The bulk of the savings come from the extra annual payment — whether that's structured as 26 fortnightly payments or 52 weekly payments, the total paid per year is nearly identical. The marginal additional saving from weekly vs fortnightly is typically a few thousand dollars over the full loan life.
To illustrate the impact of repayment frequency, consider a typical Sydney borrower scenario.
Loan amount: $750,000
Interest rate: 6.14% p.a.
Loan term: 30 years
Monthly: $4,568/month — total interest over 30 years: approximately $893,000
Fortnightly (accelerated): $2,284/fortnight — loan paid off in approximately 25 years 9 months, saving around $150,000 in interest and over 4 years of repayments.
Weekly (accelerated): $1,142/week — similar to fortnightly, with a marginally shorter payoff and a few thousand dollars additional saving.
These figures are indicative only. Adjust the calculator inputs above to model your specific loan.
If you already have a home loan and want to switch to fortnightly or weekly repayments, the process is usually straightforward.
Log into your lender's online banking or call them to confirm your current repayment frequency and amount. Some loans have a fixed direct debit that may need to be updated.
Most lenders allow you to change frequency online, via their app, or by calling their customer service team. There is generally no fee to change repayment frequency.
Ask your lender whether they apply the accelerated method (half the monthly amount fortnightly) or recalculate a separate fortnightly figure. The accelerated method is what generates the interest savings shown in this calculator.
Fortnightly repayments align well with fortnightly pay cycles for many salaried employees — meaning the repayment comes out of each pay before discretionary spending. This is one reason fortnightly is so widely used.
If you are considering refinancing at the same time as changing your repayment strategy, speak with The Kapital — there may be additional opportunities to reduce your rate or access better loan features.
Yes. When you pay fortnightly using the accelerated method — half the monthly payment, 26 times per year — you effectively make 13 monthly payments instead of 12. That one extra payment per year goes toward reducing your principal, which reduces the interest charged in every subsequent period. On a $750,000 loan at 6.14%, this typically saves over $100,000 in interest and cuts around four years off the loan term.
The difference is modest. Accelerated weekly payments (monthly ÷ 4, paid 52 times per year) save marginally more than fortnightly because you pay down principal slightly faster across the year. The practical difference in total interest saved is usually a few thousand dollars on a standard home loan — the main driver of savings is the extra annual payment, which is essentially the same whether you pay fortnightly or weekly.
Accelerated fortnightly means your fortnightly payment is exactly half your monthly payment — not a recalculated fortnightly amount that would total the same annual figure as 12 monthly payments. Because there are 26 fortnights in a year (not 24), you end up paying the equivalent of one extra monthly payment each year without it feeling like a large lump sum.
Australian banks calculate mortgage interest daily, using the formula: daily interest = outstanding balance × (annual rate ÷ 365). Interest accrues each day and is typically debited at the same frequency as your repayments. This is why reducing your outstanding balance sooner — through more frequent payments — results in less interest accruing over time.
In most cases, yes. Most Australian lenders allow you to change repayment frequency at any time through online banking or by calling. There is generally no fee. It's worth confirming whether your lender applies the accelerated method or a recalculated fortnightly figure — the accelerated method is what produces the savings shown in this calculator.
This calculator uses the standard amortisation formula with the accelerated repayment method, consistent with how major Australian lenders calculate fortnightly and weekly repayments. Results are estimates only. Actual figures depend on your lender's specific calculation method, any fees, offset account balances, and whether the interest rate changes during the loan term. For a personalised assessment, contact The Kapital.
The Kapital can help you review your current loan and identify whether a different repayment strategy — or a refinance — could save you more.
Get in touch →Sydney mortgage brokers helping first home buyers, investors, and refinancers find the right home loan.
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