Mortgage Payoff Calculator

Calculate how much time and interest you save by making extra mortgage payments. Compare extra monthly payments, lump sum paydown, and biweekly payment strategies. See your new payoff date instantly.

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Months Saved
Interest Saved
New Payoff (months)
Original Total Interest
Extended More scenarios, charts & detailed breakdown
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Months Saved
Interest Saved
New Payoff (months)
Professional Full parameters & maximum detail
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Current Mortgage

Standard Total Interest Remaining

Extra Payment Strategy

Interest Saved with Extra Payments
Payoff with Extra Payments (months)

Refinance vs Extra Payment

Net Savings Refinancing (vs staying)

Payoff by Target Date

Required Extra Payment for Target Date

How to Use This Calculator

  1. Enter your remaining balance, interest rate, remaining months, and extra monthly payment to instantly see months saved and interest saved.
  2. Use the Extra Monthly tab to model different extra payment amounts.
  3. Use the Lump Sum tab to see the impact of a one-time principal payment.
  4. Use the Biweekly Payments tab — paying every two weeks adds one extra payment per year automatically.
  5. Use the Professional tab to compare extra payments vs refinancing and calculate the exact extra payment needed to hit a target payoff date.

Formula

Standard Payment = P × r × (1+r)^n / ((1+r)^n − 1)
Months Saved = Standard Months − Accelerated Months
Interest Saved = Standard Total Interest − Accelerated Total Interest

Example

Example: $280,000 remaining balance, 6.8% rate, 300 months remaining. Extra $200/month → new payoff in ~256 months (44 months saved), saving approximately $47,200 in interest.

Frequently Asked Questions

  • Extra payments go directly toward principal, dramatically reducing interest paid over the life of the loan. On a $280,000 mortgage at 6.8% with 25 years remaining, paying an extra $200/month saves approximately $47,000 in interest and cuts 4–5 years off the loan. Even $100/month extra can save $25,000+.
  • It depends on the interest rate difference and closing costs. If you can refinance to a significantly lower rate (1%+ reduction) and plan to stay in the home long enough to recoup closing costs ($3,000–$6,000 typically), refinancing wins. If rates are similar, extra payments cost nothing and give you flexibility.
  • Instead of 12 monthly payments, biweekly payments result in 26 half-payments per year — the equivalent of 13 full monthly payments. This one extra payment per year reduces a 30-year mortgage by 4–6 years and can save $30,000–$60,000 in interest on a typical mortgage.
  • Yes, most mortgages allow extra principal payments at any time without penalty. Always specify the extra amount is for "principal only" when submitting payments — otherwise the servicer may apply it to future months' interest. Verify this policy with your lender, especially for FHA or VA loans.

Related Calculators

Sources & References (5)
  1. CFPB — Paying Off Your Mortgage Early — Consumer Financial Protection Bureau
  2. Fannie Mae — Mortgage Payoff Guidance — Fannie Mae
  3. IRS Publication 936 — Home Mortgage Interest Deduction — Internal Revenue Service
  4. Federal Reserve — Mortgage Market Data — Federal Reserve
  5. HUD — Homeowner Financial Counseling — U.S. Department of Housing and Urban Development