This mortgage payoff calculator shows what extra payments do to your mortgage: add a monthly extra amount (or a one-time lump sum) and see your new payoff date, how many years you shave off, and exactly how much interest you save.
What Is a Mortgage Payoff Calculator?
A mortgage payoff calculator answers the question every homeowner eventually asks: what if I pay a bit extra? Because mortgage interest is charged on the remaining balance, extra principal early in the loan removes years of interest at the far end. This calculator quantifies that trade precisely for your balance, rate and remaining term. It is part of our Finance Calculators collection, alongside the Mortgage Calculator for new loans.
Worked Example (Verified)
A $300,000 mortgage at 6% with 30 years remaining: payment $1,798.65/month, total interest $347,515 if you never pay extra.
- Add $200/month: the loan ends in 279 months (23 years, 3 months) — 6 years 9 months early
- Total interest falls to $256,341 → you save $91,174
- That is the quiet math of amortization: the extra $200 attacks principal directly, and every later month’s interest is computed on a smaller balance.
For the full month-by-month schedule behind numbers like these, use our Amortization Calculator.
Ways to Pay Off a Mortgage Faster
- Fixed monthly extra: the method in this calculator — simple, automatic, powerful.
- Biweekly half-payments: 26 half-payments a year = 13 full payments — one extra month per year without feeling it.
- Lump sums: bonuses, tax refunds, an inheritance — the lump-sum field above shows their effect instantly. Early lump sums beat late ones, because they kill more future interest.
- Round up: paying $1,900 instead of $1,798.65 is the same trick in disguise (~$100/month here).
- Refinancing to a shorter term usually beats extra payments on rate, but restarts closing costs — compare total interest both ways.
Should You Pay Extra? The Honest Trade-Offs
- Extra payments earn a guaranteed return equal to your mortgage rate — 6% here, risk-free and after-tax simple.
- But the money becomes illiquid home equity; keep your emergency fund and high-interest debt handled first (cards belong in the Debt Payoff Calculator — 24% APR beats 6% mortgage every time).
- Check for prepayment penalties (rare on modern US mortgages, but verify) and tell your servicer to apply extras to principal, not future payments.
Related Tools
- Amortization Calculator — full payment schedule
- Mortgage Calculator — payments for a new loan
- Debt Payoff Calculator — snowball vs avalanche for other debts
Frequently Asked Questions
How much does $200 extra a month save on a mortgage?
On a $300,000 loan at 6% over 30 years: about $91,174 of interest and 6 years 9 months of payments. Your numbers will differ — enter them above.
Is it better to pay extra monthly or one lump sum?
A lump sum today is mathematically stronger than the same total spread over years, because it removes principal (and its future interest) immediately. Monthly extras win on habit and cash flow.
Do extra payments shorten the term or lower the payment?
On a standard fixed mortgage, the required payment stays the same and the term shortens — which is where the interest savings come from. (Some lenders offer a paid “recast” to lower the payment instead.)
Should I pay off my mortgage or invest?
Paying extra earns your mortgage rate, guaranteed. Investing may earn more on average but with risk and taxes. Many people split the difference — and eliminate higher-rate debts first regardless.
Does this calculator include taxes and insurance?
No — it models principal and interest only, like most payoff math, because escrow amounts do not change with extra principal payments.
Is this mortgage payoff calculator free?
Yes — free, instant, no sign-up. It provides estimates, not financial advice.