See how much time and interest you save by making extra mortgage payments.
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关于此工具
The Mortgage Overpayment Calculator helps homeowners understand the powerful impact of paying extra each month toward their mortgage principal. Enter your current loan balance, annual interest rate, remaining term in years, and the extra monthly amount you plan to overpay. The calculator instantly shows how many years and months you will shave off your loan and the total interest savings. A side-by-side comparison table shows the normal payoff schedule versus the accelerated schedule, and a month-by-month breakdown for the first 12 months shows exactly how each payment splits between principal and interest. All calculations run in your browser with no data sent to any server.
使用方法
1Enter your current outstanding loan balance.
2Enter your annual interest rate as a percentage.
3Enter the remaining term in years.
4Enter the extra monthly overpayment amount.
5Read the years saved and interest saved summary at the top.
6Scroll down to compare the normal and overpayment schedules side by side.
常见问题
The calculator runs two full amortization schedules — one with your regular monthly payment and one with the overpayment added — and subtracts the total interest paid under the accelerated schedule from the total under the normal schedule. The difference is your interest saving.
Yes, provided the overpayment is applied directly to the principal. Every extra pound or dollar reduces the outstanding balance, which means less interest accrues in the following months, so a larger share of each future payment clears principal, creating a compounding acceleration effect.
Many lenders allow overpayments of up to 10% of the outstanding balance per year without penalty. Check your mortgage terms. This calculator does not model early repayment charges, so subtract any fees from your savings figure to get the true net benefit.
The calculator uses a standard fixed-rate amortization formula, so it is most accurate for fixed-rate mortgages. For tracker or variable-rate mortgages the result is an estimate based on the current rate staying constant.
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