Daily Figures Edition No Sign-Up • Free Forever Vol. XII — No. 204
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Extra Mortgage Payment Calculator

See how much time and interest an extra monthly payment saves.

Filed by The Statistics Desk  |  Method: amortization with and without extra
Interest saved
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With the extra payment.
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New payoff—
Monthly payment—
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Educational estimate — not a loan offerEverything computed client-side — nothing leaves this page

How the Extra Mortgage Payment Calculator Works

Every extra dollar you put toward principal skips all the future interest that dollar would have accrued, so small extra payments shorten the loan surprisingly fast. This calculator amortizes your loan twice — once with the normal payment and once with your extra amount added each month — and reports the time and interest you save. Adding $200 a month to a $300,000 loan at 6.5% pays it off about 6 years early and saves well over $100,000 in interest.

The savings come from paying the balance down faster, which cuts the interest charged on it every following month. Make sure extra payments are applied to principal, not held toward the next installment. Even occasional lump sums help.

extra principal shortens the term and cuts total interest

Frequently Asked Questions

How much do extra mortgage payments save?

Each extra payment goes straight to principal, avoiding all its future interest. This calculator shows the exact time and interest saved for your loan and extra amount.

Is it better to pay extra monthly or a lump sum?

Both help; consistent monthly extra payments tend to save the most because the principal drops sooner and stays lower every month afterward.

Should I make sure the extra goes to principal?

Yes — tell your servicer to apply extra payments to principal. Otherwise some lenders credit them toward the next scheduled payment, which doesn’t save interest.

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