Payment Frequency Calculator

See how weekly or fortnightly payments can save you money on your mortgage

Paying weekly or fortnightly instead of monthly means you effectively make 13 months of payments per year instead of 12, reducing your loan term and total interest paid.

Loan Amount

Interest Rate (%)

Loan Term (Years)

Interest Savings with Weekly Payments

$766

Pay off 0.0 years earlier

Payment Comparison

Monthly

12 payments/year

$3,160

$37,924/year

Fortnightly

26 payments/year

$1,458

$37,906/year

Weekly

52 payments/year

$729

$37,899/year

Fortnightly Savings

$536

0.0 yrs faster

Weekly Savings

$766

0.0 yrs faster

Total Interest Paid

Monthly (30 years)$637,722

Fortnightly (30.0 years)$637,186

Weekly (30.0 years)$636,957

Why Does This Work?

With weekly payments, you pay $729 × 52 = $37,899 per year, which is -$26 more than 12 monthly payments. This extra amount goes directly to paying down your principal faster.

How payment frequency changes the result

Changing from monthly to weekly or fortnightly can improve the outcome because you reduce the loan balance a little sooner and often end up making the equivalent of an extra month of repayments each year.

Weekly and fortnightly payments can reduce interest over the life of the loan.
More frequent payments may shorten the repayment term.
The exact result depends on lender processing rules and whether repayments are recalculated correctly.

What to check before switching repayment frequency

A frequency change is usually simple, but it still helps to confirm how your lender applies the payments and whether the new rhythm fits your income cycle.

Check whether your bank uses true weekly or fortnightly calculations.
Match repayments to your pay cycle so the habit is sustainable.
Keep a buffer so more frequent payments do not create cash-flow stress.

Payment frequency FAQs

Is fortnightly better than monthly for a mortgage?

It often is, because fortnightly repayments can reduce interest and help pay the loan down earlier, especially if the lender applies true fortnightly calculations.

Why do weekly payments sometimes save more interest?

Weekly payments reduce the balance more frequently, so less interest can accrue over time compared with a monthly schedule.

Does changing payment frequency always mean I pay an extra month each year?

Often yes in practical terms, but the exact effect depends on the lender's repayment method and how the periodic payment is calculated.

Disclaimer: This calculator provides estimates only and should not be relied upon for financial decisions. Actual loan terms, rates, and eligibility may vary. Please contact a Mortgage Lab adviser for personalised advice.