Extra Mortgage Payment Calculator

See how much time and interest you could save by making additional principal payments each month.

Mortgage Details

Loan Amount

Annual Interest Rate

Enter the mortgage interest rate (note rate), not APR

Loan Term

Years

Months

Quick select:

Extra Monthly Payment

Additional principal payment each month

Comparison

StandardWith Extra Payment

Monthly P&I$1,945.79

Monthly P&I$2,145.79+$200.00 extra

Payoff DateAugust 2056

Payoff DateAugust 2049

Total Interest$400,485.94

Total Interest$290,558.43

Payments360 months

Payments276 months

Savings

Time Saved7 years

Interest Saved$109,927.52

Accelerated Schedule

How Extra Payments Work

Standard mortgage payments follow an amortization schedule — each payment covers interest first, with the remainder going to principal. Making extra principal payments reduces the outstanding balance, which means less interest accrues in future months.

Even small extra payments, applied consistently, compound over time. Because interest is front-loaded on long-term mortgages, reducing the balance early has an outsized impact on lifetime interest costs. Use the Amortization Calculator to see how extra payments change the remaining-balance schedule.

Frequently Asked Questions

: On a $300,000, 30-year loan at 6.75%, the scheduled P&I is about $1,945.79. An extra $100 per month pays the loan off in about 311 months instead of 360, saving about 4 years and 1 month and approximately $65,000 in interest. Exact savings depend on your loan details.
: Yes. Extra payments made earlier in the loan term save more interest because interest is calculated on a higher balance. However, extra payments made at any point still reduce your total interest and shorten your payoff.
: Extra payments should be applied to principal only. When you make an extra payment, notify your loan servicer in writing that the additional amount should be applied to principal, not applied to future payments. Verify how your servicer handles extra principal payments.
: Extra principal payments can reduce future interest and shorten your payoff period. Check your loan terms for any prepayment restrictions and confirm how your mortgage servicer applies additional payments. Whether extra payments or investing is a better fit depends on your rate, taxes, liquidity needs, and risk tolerance.