Car Loan Early Payoff Calculator
Calculate time and interest saved by making extra car loan payments.
Enter balance, rate, and extra monthly payment to see payoff date and total savings.
Early car loan payoff works by making additional principal payments beyond your required monthly payment. Because auto loan interest is calculated on the remaining principal balance, every extra dollar paid toward principal immediately reduces the amount of interest that accrues in all future months.
Standard loan amortization formula:
Monthly Payment = P × [r(1+r)^n] / [(1+r)^n − 1]
Where P = principal, r = monthly interest rate (annual rate ÷ 12), n = total number of payments.
Interest paid per month:
Monthly Interest = Remaining Balance × Monthly Rate
This is why early payments are especially powerful: the first payments are almost entirely interest, while later payments are mostly principal.
Impact of extra monthly payments on a $28,000 loan at 7.5% APR, 60 months ($560/month standard payment):
| Extra Payment | Payoff | Interest Paid | Interest Saved | Months Saved |
|---|---|---|---|---|
| $0 extra | 60 months | $5,618 | — | — |
| $50/month | 54 months | $4,958 | $660 | 6 months |
| $100/month | 49 months | $4,424 | $1,194 | 11 months |
| $200/month | 41 months | $3,510 | $2,108 | 19 months |
| $500/month | 30 months | $2,284 | $3,334 | 30 months |
Strategies for extra payments:
- Round up your payment: If your payment is $386, pay $400 every month — painless and adds up
- One extra payment per year: Prepay one full monthly payment each January — typically saves 4–6 months
- Apply windfalls: Tax refunds, bonuses, and gifts applied directly to principal
- Biweekly payments: Pay half the monthly amount every two weeks — this results in 13 full payments per year instead of 12
Important steps before making extra payments:
- Check for prepayment penalties: Rare on modern auto loans but worth confirming with your lender
- Specify “apply to principal”: Extra payments must be labeled as additional principal, not as “next month’s payment”
- Call or go online: Lenders often require explicit instruction to apply overpayments to principal balance
- Build emergency fund first: Liquid savings take priority over debt payoff below 10% interest
The opportunity cost question: If your loan rate is 4% and your savings/investment account earns 5–7%, paying off the loan early may actually cost you money in comparison. For rates above 6–7%, early payoff is almost always the mathematically better choice.