Mortgage Payoff Calculator

Mortgage Payoff Calculator

This calculator shows how extra monthly payments can accelerate your mortgage payoff and dramatically reduce the total interest you pay. Enter your remaining balance, interest rate, remaining term, and an extra payment amount to see exactly how many years you can shave off your mortgage.

How Early Payoff Is Calculated

Your base monthly payment is computed using the standard amortization formula: M = P[r(1+r)^n] / [(1+r)^n - 1], where P is the balance, r is the monthly interest rate, and n is the total months. The calculator then simulates month-by-month payments with and without the extra amount, comparing total interest paid under each scenario.

Each month, interest accrues on the remaining balance, and the extra payment goes entirely toward principal — which is why even small extra payments have a compounding effect over time.

Example

Key Factors That Affect Mortgage Payoff

• Extra payment amount — even $100/month extra can cut years off a 30-year mortgage
• Interest rate — higher rates mean more interest savings from early payoff
• Remaining balance — larger balances benefit more from extra payments in absolute dollar terms
• Remaining term — the earlier you start extra payments, the greater the compounding savings
• Payment consistency — making extra payments every month is more effective than occasional lump sums

Tips

1. Even an extra $100 per month on a $250,000 mortgage at 6.5% saves roughly $45,000 in interest
2. Apply windfalls like tax refunds or bonuses as lump-sum principal payments for maximum impact
3. Confirm with your lender that extra payments go toward principal, not future interest
4. Compare the interest saved from early payoff against potential investment returns before committing all extra cash