Mortgage Payoff Calculator
See how much interest you save and how much sooner your mortgage is paid off by adding extra monthly or one-time payments.
Why extra payments save so much
Every extra dollar you pay goes directly to principal. That dollar then stops generating interest for every remaining month of the loan, so its effect compounds. Paying extra on a mortgage is effectively a guaranteed, tax-free return equal to your interest rate.
Example
With $300,000 left at 6.5% and 28 years to go, the payment is $1,941.05. Adding just $200 a month pays the loan off 6 years sooner and saves about $88,000 in interest.
Popular payoff strategies
- Fixed extra amount: add a set amount each month, such as $100 or $200. Simple and effective.
- Biweekly payments: paying half the monthly payment every two weeks makes 26 half-payments, or 13 full payments a year. That one extra payment typically cuts four to six years from a 30-year loan. Check that your lender applies the payments as they arrive.
- Round up: rounding a $1,941 payment to $2,000 adds $59 a month painlessly.
- Windfalls: put part of tax refunds or bonuses toward principal as a one-time payment.
When paying off early is not the best move
Before prepaying, make sure you have an emergency fund, are capturing any employer 401(k) match and have no high-interest debt such as credit cards. If your mortgage rate is low, say 3%, investing the extra money may earn more over time, though without a guarantee. Also confirm your loan has no prepayment penalty, and tell your lender to apply extra money to principal, not to next month's payment.
Frequently asked questions
How much does an extra $100 a month save on a mortgage?
On a typical $300,000 30-year loan at 6.5%, an extra $100 a month saves about $61,000 in interest and cuts about 4 years off the loan. Enter your own numbers above for an exact figure.
Is it better to make biweekly payments?
Biweekly payments add one extra monthly payment per year, which shortens the loan significantly. You get the same effect by adding one-twelfth of your payment to each monthly payment.
Should I pay off my mortgage early or invest?
It depends on your rate and risk tolerance. Prepaying gives a guaranteed return equal to your rate; investing may earn more but can lose value. Many people do some of both.
Last reviewed Oct 20, 2026. Results are estimates; check important decisions with a qualified professional.