Mortgage Interest Total Calculator
Calculate the total interest you will pay over the life of a mortgage based on the loan amount, interest rate and repayment term.
Your results
Calculation breakdown
- Total interest
- Sum of interest charged in every month of the amortisation schedule
Worked example
A $500,000 loan at 6% over 30 years costs about $579,000 in total interest, more than the amount borrowed.
Assumptions
- Assumes no extra repayments and a constant interest rate for the full term.
How this calculator works
This calculator estimates the total interest paid over the full term of a standard principal and interest mortgage, giving you a single figure for the overall cost of borrowing on top of the amount you borrowed.
Frequently asked questions
Why is total interest often larger than the loan amount?
Over a long term such as 30 years, compounding interest on a large balance can add up to more than the original principal, especially at higher interest rates.
Does making extra repayments reduce this figure?
Yes, any extra repayments reduce the balance faster and lower the total interest paid; use the lump sum or extra repayment calculators to model that.
Is this the same as the comparison rate?
No, this is the dollar amount of interest paid over the loan, while a comparison rate is a percentage figure that also includes fees.
Results are estimates only and are not financial, tax, legal or credit advice.