Mortgage Payoff Calculator
See how extra payments on your mortgage can save you thousands in interest and years of payments.
Before you calculate
Extra payments are assumed to reduce principal immediately. Confirm payment allocation and any prepayment penalty with your servicer.
Extra Mortgage Payments
Every dollar of extra principal payment reduces the balance on which interest is charged. Early in the loan, most of the standard payment is interest — extra principal payments exponentially accelerate payoff by reducing the interest-earning balance each month.
Monthly Interest = Remaining Balance × (Rate / 12) | Earlier payoff from extra payments reduces compounding base each subsequent monthExample Scenarios
$200/Month Extra
On a $280,000 / 30-year / 7% mortgage, paying an extra $200/month saves roughly 5–6 years of payments and over $80,000 in interest. Small extra payments have outsized impact due to compound interest.
Annual Lump Sum
Making one extra mortgage payment per year (equivalent to ~$200/month extra on average) follows the same principle. Many homeowners use tax refunds or bonuses for this purpose.
Methodology & Assumptions
Amortization is recomputed month-by-month adding the extra payment to principal. New payoff month is when balance reaches zero. Interest saved is the difference in total interest paid.
Sources & calculation notes
Maintained by MoneyCalc. Results are estimates based on the inputs and assumptions shown, not personalized financial advice or a lender quote. Default rates are examples unless a specific tax year or official table is identified.
References explain the underlying concepts or rules. They do not endorse or independently certify this implementation.
Calculations run in your browser. Some tools retain settings on this device. Displayed rounding can produce small differences from a statement or contract.