Extra Mortgage Payment Calculator 2026
See how much interest you save and how early you pay off your mortgage by making extra payments monthly, annually, or as a one-time lump sum.
The Most Efficient Way to Make Extra Payments
Extra payments are most powerful early in your loan when your balance is highest. A $200 extra payment in year 1 of a 30-year mortgage saves nearly twice as much as the same payment in year 15, because it prevents compounding on a larger balance for a longer period.
Key rule: Always specify "apply to principal" on extra payments. Some servicers apply extra funds to future scheduled payments instead, which doesn't reduce principal efficiently.
Frequently Asked Questions
On a $300,000 30-year mortgage at 7%, paying $200 extra per month saves approximately $87,000 in interest and pays off the loan 6 years early. The savings are front-loaded — extra payments early in the loan save far more than the same payments made later.
It depends on your mortgage rate vs expected investment return. If your mortgage is 7% and you expect 8–10% stock market returns, investing has a higher expected return. If your mortgage is 3–4%, the math clearly favors investing. However, paying off the mortgage provides a guaranteed, risk-free return equal to your interest rate.
When submitting extra payments, include a note specifying "apply to principal only." Online banking systems usually have a payment type selector. Call your servicer to confirm — some automatically apply overpayments to next month's payment instead of reducing principal, which eliminates the interest-saving benefit.
Biweekly payments mean you pay half your monthly payment every two weeks. Since there are 26 biweekly periods per year, you make the equivalent of 13 monthly payments per year instead of 12 — one extra full payment annually. On a 30-year, $300,000 mortgage at 7%, this saves approximately $40,000 in interest and cuts 4–5 years off the loan.