Extra Payment Payoff Calculator
Extra principal shortens a loan because it removes future interest. Model monthly, annual or one-time extra payments and compare the payoff against the standard schedule.
The loan
Extra principal
Extra principal is applied on top of the scheduled payment. Leave a field at zero to skip it.
Estimated interest saved
$108,917
Paying extra could shorten the loan by about 6 yr 1 mo, paying it off in 23 yr 11 mo instead of 30 years.
Standard vs. with extra payments
| Measure | Standard | With extra |
|---|---|---|
| Payoff time | 30 years | 23 yr 11 mo |
| Total interest | $459,160 | $350,243 |
| Total of all payments | $819,160 | $710,243 |
Payment detail
- Scheduled payment (P&I)
- $2,275/mo
- Extra each month
- $200/mo
- Total extra principal paid
- $57,200
- Interest saved
- $108,917
- Time saved
- 6 yr 1 mo
- Assumed rate
- 6.500%
Want to understand this number?
How this calculator works
The calculator builds two month-by-month schedules from the same loan. In both, monthly interest is the remaining balance times the rate divided by twelve. In the second schedule, any extra principal you enter is subtracted from the balance in the month it is paid.
Because the balance drops faster, less interest accrues in every later month. Interest saved is simply the difference between the two totals; time saved is the difference in the number of payments.
What it can't tell you
- Some loans or servicers require you to designate extra funds as principal, and a few older loans carry prepayment penalties.
- Extra principal does not lower your required monthly payment unless the loan is formally recast.
- Money used for extra principal is no longer liquid; an emergency fund and higher-interest debt usually come first.
- Results ignore taxes, insurance, mortgage insurance and any investment return you might have earned instead.