Free Mortgage Payoff Calculator
Enter your balance, rate, and monthly payment, plus any extra you can pay, to see your payoff date and exactly how much interest you save.
This free mortgage payoff calculator amortizes your loan month by month with and without extra payments, showing your payoff date, total interest in each scenario, interest saved, and months shaved off, so you can see what an extra $100 a month really buys.
Principal and interest only, not taxes or insurance.
Estimates for planning only. Taxes, insurance, PMI, and adjustable rates are not modeled; confirm details with your lender.
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How extra mortgage payments actually work
Every mortgage payment splits into interest and principal. Early in the loan, most of the payment is interest: on a $300,000 loan at 7 percent, the first month's interest alone is $1,750. Extra payments go entirely to principal, which is why they are so powerful early, when the interest portion is largest.
Paying principal early shrinks every future interest charge, because interest is calculated on the remaining balance each month. An extra $200 a month on that $300,000, 7 percent, 30-year loan cuts the payoff from 30 years to about 23 years and saves roughly $117,000 in interest. The same $200 matters far less in year 25, when the balance is small.
Biweekly payments are a painless way to pay extra: 26 half-payments a year equals 13 full monthly payments instead of 12. That one extra payment a year typically shaves about 6 years off a 30-year loan with no change to your monthly budget rhythm.
Before you accelerate, check three things. First, prepayment penalties: rare on modern US mortgages but verify. Second, higher-interest debt: credit card balances at 20 percent-plus should usually go first. Third, your emergency fund and retirement match: an extra payment earns your mortgage rate, risk-free, which beats savings accounts but may trail market returns.
Where the extra payment goes matters: tell your servicer in writing to apply it to principal, not as an early next payment. Some servicers default to holding partial extra payments in suspense until they total a full payment, which blunts the benefit.
Mortgage payoff questions
How much do extra mortgage payments save?
It depends on the loan, but the effect is large early: on a $300,000, 7 percent, 30-year loan, an extra $200 a month saves roughly $96,000 in interest and cuts about 6 years off the payoff.
Is it better to pay extra monthly or make one lump payment?
Monthly extra payments save slightly more than one annual lump sum of the same total, because the principal (and thus the interest) drops a little sooner each month. The difference is modest either way.
Do biweekly mortgage payments really help?
Yes. Paying half your mortgage every two weeks makes 26 half-payments, equal to 13 full monthly payments per year. That one extra payment annually typically shaves 4 to 6 years off a 30-year loan.
Should I pay off my mortgage early or invest?
An extra payment earns a guaranteed return equal to your mortgage rate. Investing might earn more but with risk. Most advisors say: build an emergency fund, capture any 401(k) match, kill debt above your mortgage rate, then decide.