Mortgage Payoff Calculator

Estimate your mortgage payoff date, total interest, time saved, and interest savings when you add extra payments.

How to Use

  1. Enter your mortgage balance, rate, and regular payment.
  2. Add any optional extra monthly payment or annual lump sum.
  3. Choose your payment frequency and start month.
  4. Review the payoff date, time saved, and interest saved.
Payoff Summary
Mortgage Acceleration View
Compare your current plan against an accelerated payoff strategy.
Payoff Date
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Time Saved
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Interest Saved
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Total Paid
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Standard payoff —
Accelerated payoff —
Months Remaining
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Payments Remaining
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Total Interest
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Extra Paid
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Inputs & Settings
Enter current loan details and optional extra payments.
Original principal at the start of the mortgage.
Leave blank to use the original balance as the current balance.
Annual mortgage rate as a percentage.
Principal and interest payment only unless you choose otherwise in your own workflow.
Optional extra amount added to each payment.
Optional once-per-year principal reduction.
Used for payment count and payoff schedule math.
Used to estimate the payoff month and year.
Month when the annual extra principal payment is applied.
Extra Payment
$200
Annual Lump Sum
$0
Show Work (step-by-step)
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Work is shown using periodic interest rate, payment frequency, and remaining balance assumptions entered above.

Formulas & Reference

Quick answer: Mortgage payoff depends on your remaining balance, interest rate, payment amount, payment frequency, and any extra principal payments.

This tool compares a standard payoff path against an accelerated payoff path using your extra payment inputs.

  • Periodic interest rate: annual rate ÷ payments per year
  • Interest per period: current balance × periodic rate
  • Principal paid per period: payment − interest
  • New balance: old balance − principal paid − extra principal
  • Total interest: sum of all interest charges until balance reaches zero
This is an educational planning tool. Actual lender servicing, escrow, fees, compounding method, and payment posting rules may vary.

FAQ

Does an extra payment always reduce interest?

Usually yes, if the lender applies the extra amount directly to principal. Reducing principal earlier lowers future interest charges.

What is the difference between extra monthly payments and a yearly lump sum?

Monthly extra payments reduce balance sooner throughout the year. A lump sum can still help a lot, but timing affects total savings.

Can I use this for biweekly mortgage payments?

Yes. Select biweekly or weekly frequency to estimate how more frequent payments may change the payoff timeline.

Does this include taxes, insurance, or HOA fees?

No. This payoff model is intended for principal and interest payoff planning. Escrow items do not reduce principal.

Tool Info

Last updated:

Updates may include payoff modeling improvements, frequency handling, and edge-case validation.