Debt payoff: how extra payments change the numbers
Understand the mathematics behind repayment time and why regular extra payments can change the total interest paid.
Why the monthly payment is not all principal
When interest is charged periodically, part of a repayment covers that interest and the remainder reduces the balance. As the balance falls, the interest portion can fall too, assuming the rate stays constant.
What an extra payment can do
An additional payment can reduce the outstanding balance faster. A lower balance can then reduce future interest charges when the interest calculation is based on the remaining principal.
Watch for payment rules
Actual lenders can have fees, settlement rules, rate changes or payment timing that differ from a simple calculator. Check how extra payments are applied.
Compare scenarios
Test several repayment amounts rather than focusing on one headline number. Looking at payoff time and estimated interest together shows the trade-off more clearly.
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