Monthly repayment, total interest paid, principal paid down year-by-year. Excludes fees, redraw, offset, lender LMI. For exact lender quotes, talk to a broker — for ballpark planning, this is the math the banks use.
Same loan, different frequencies. Fortnightly + weekly pay off slightly faster — there are 26 fortnights vs 12 months × 2, so you effectively pay an extra month's worth a year.
P&I (Principal & Interest) is the most common Australian home loan structure. Each repayment includes both the interest charged that period AND a small chunk of the principal you owe. Over a typical 30-year term, your loan amortises — meaning the principal balance reduces to zero by the final repayment.
The alternative is Interest Only (IO), where you only pay the interest for a set period (typically 1-5 years). IO suits some investors during the accumulation phase but doesn't build equity and means a higher loan balance at the end of the IO period.
On a $640,000 loan at 6.30% over 30 years, the first monthly repayment is $3,961. Of that, roughly $3,360 is interest and only $601 is principal. As the loan progresses, the principal portion grows and the interest portion shrinks — the "amortisation curve."
By year 15, you've paid off about 27% of the original principal. By year 25, you've paid about 70%. The final 5 years repay nearly half of the entire loan because almost all of each payment is now going to principal.
If you split your monthly repayment in half and pay fortnightly, you'll make 26 fortnightly payments per year — equivalent to 13 monthly payments instead of 12. That extra month per year shaves about 4-5 years off a 30-year loan and saves tens of thousands in interest. Many lenders let you set this up automatically.