Mortgage Early Payoff Calculator
See exactly how many months you shave off your mortgage and how much interest you save by making extra payments — monthly, yearly, or one-time lump sums.
| Year | Standard balance | With extra payments balance | Interest saved (cumulative) | Status |
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Why extra payments are so powerful
Every dollar of extra principal payment saves you the full remaining interest on that dollar — which on a 30-year mortgage at 6.58% is roughly $1.07 in interest saved for every $1 paid early. That’s a guaranteed, tax-free 6.58% return. No stock market investment offers a guaranteed return — making extra mortgage payments is one of the best risk-free investments available when your rate is above ~5%.
The best strategies for extra payments
The most powerful time to make extra payments is early in the loan when your balance is highest and the interest savings compound over more years. A $200/month extra payment starting in month 1 saves dramatically more than starting in year 10. Annual lump sums from tax refunds are also highly effective — even $3,000/year extra can shave 7–8 years off a 30-year mortgage.