The most underrated money move in home ownership: what does an extra $100 or $200 a month actually do?
Every extra dollar goes straight to principal — and every dollar of principal you kill today stops earning interest against you for the entire remaining life of the loan. That's why extra payments early beat extra payments late.
Tip: even one extra payment per year (divide your monthly payment by 12 and add that) typically cuts 4–6 years off a 30-year mortgage. Check with your lender that extra payments are applied to principal, not "next month's payment."
Estimates are for education, not financial advice.
🤝 No signup. No spam. Nothing here tries to sell you a loan.
Every dollar of extra principal you pay erases the interest that dollar would have generated for the rest of the loan. Early in a mortgage, when your balance is high and almost all of each payment is interest, that effect is enormous — a little extra now removes many months of future interest. This calculator adds your extra monthly amount straight to principal and shows two things that make people sit up: how many years earlier you'd be debt-free, and how much total interest you'd never pay.
On a $320,000 loan at 6.5% over 30 years, adding just $200 a month to principal typically shaves roughly five to six years off the loan and saves well over $80,000 in interest — for about the price of a couple of restaurant meals a month. Bigger extra payments compound the effect. The trick is that the money must go to principal, not ahead on your next payment, so tell your servicer to apply it that way.
Is there a penalty for paying early?
Almost no modern U.S. mortgage has a prepayment penalty, but it's worth a one-line check with your servicer before you start.
Extra monthly, or one lump sum?
Both help; monthly is easier to sustain and starts saving immediately. Even irregular extra payments whenever you have spare cash move the needle.
Should I pay extra or invest instead?
It depends on your rate versus expected investment returns and your appetite for risk. Guaranteed interest saved is a real, risk-free return — compare it honestly to what else you'd do with the money.