Mortgage Payoff Calculator (Extra Payments)
See how much interest and time you save by paying extra on your mortgage each month.
How extra payments shorten a mortgage
Each extra dollar goes straight to principal, which stops interest being charged on that amount for the rest of the loan. Because early payments are mostly interest, extra money paid early has the biggest effect.
Before you overpay
Check for prepayment penalties and ask your lender to apply extra payments to principal. Compare the guaranteed saving with what the same money could earn elsewhere, and keep an emergency fund first.
Worked example
Last reviewed November 2026. Formulas are standard and shown in the sections above; results are estimates.
Tips and common mistakes
- Tell your lender extra payments are for principal.
- A single extra payment per year also helps.
- Keep your emergency fund before overpaying.
Frequently asked questions
Is paying extra on a mortgage worth it?
It gives a guaranteed return equal to your mortgage rate. Compare that with other uses of the money.
Does it work for any fixed-rate loan?
Yes. Enter the balance, rate and years remaining.
What about biweekly payments?
Paying half every two weeks makes one extra monthly payment a year. Enter that as the monthly extra.
Money guides for this topic
All guides →Buying a Home or Car: The Math Before You Sign
How to work out what you can really afford for a home or car, using simple rules and real numbers.
Read guide →How Loan Interest Really Works
Understand APR, amortization and why early payments are mostly interest, with tips to pay less.
Read guide →How to Save Money: 10 Practical Ways with Real Numbers
Ten proven ways to save money, each with the math showing how much you can keep every year.
Read guide →Related calculators
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Open calculator →Results are estimates and not financial advice.