Mortgage Extra Payment Calculator
Calculate total interest savings and payoff timeline acceleration from making extra monthly or lump-sum mortgage principal prepayments.
Maintain your extra payment routine to save tens of thousands in finance charges.
Your extra prepayment strategy yields over $25,000 in total compound interest savings.
How to Use the Mortgage Extra Payment Calculator
Making extra principal prepayments directly reduces your outstanding loan balance, shrinking total compound interest accrued and shortening your debt duration. Use this calculator to model extra monthly payments or annual lump sums and see your accelerated payoff schedule.
- Current Loan Principal ($): Bounded parameter in the mathematical model.
- Interest Rate (%): Bounded parameter in the mathematical model.
- Remaining Term (Years): Bounded parameter in the mathematical model.
- Extra Monthly Payment ($): Bounded parameter in the mathematical model.
- Annual Lump-Sum Prepayment ($): Bounded parameter in the mathematical model.
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Step-by-step mathematical walkthroughs of 30-year fixed, 15-year accelerated, extra prepayment payoff, refinance break-even, and low down payment PMI scenarios.
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Read Full Guide →How do extra payments affect my monthly payment amount?
Extra principal prepayments do not change your required monthly payment amount. Instead, they reduce your remaining balance and shorten your overall loan term.
Is it better to pay extra monthly or as an annual lump sum?
Paying extra monthly compounds interest savings slightly faster because principal is reduced sooner, but both methods save significant compound interest.
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