Quick answer: refinancing can lower your payment without lowering your remaining borrowing cost. Compare a dated payoff quote and the cost of keeping your current loan with the new loan's full payment schedule, fees and payoff date. This page is a worked guide; it does not provide a dedicated refinance calculator.
Table of Contents
Start with the balance you would refinance today
Ask your current lender for a payoff quote and its expiration date. The payoff may differ from your statement balance because interest or charges have accrued. Record your current payment, contractual interest rate, months remaining and any prepayment charge. For each new offer, collect the amount financed, interest rate, APR, payment schedule, loan term and every fee. The CFPB's auto-loan disclosure guide explains the APR, finance charge, amount financed and total of payments to check before signing.
Compare from the same starting date. Count only the payments and costs still ahead on the current loan. Do not compare a new loan's full cost with interest you already paid on the old loan. Test a new term equal to the months remaining first; then test any longer term separately.
A hypothetical $18,000 comparison
Assume today's principal balance and payoff are both $18,000, with exactly 48 monthly payments left. There is no accrued payoff interest, fee, penalty, extra payment or change in payment dates. All rates below are fixed nominal contract interest rates; this fee-free illustration assumes APR equals that rate. Interest is calculated monthly on the remaining balance, rounded to cents each month, with a regular payment rounded to cents and the final payment adjusted to clear the balance. A real contract may accrue interest daily and produce different figures.
| Choice from today | Contract rate / months | Regular monthly payment | Final payment | Remaining interest | Total payments from today |
|---|---|---|---|---|---|
| Keep current loan | 13.5% / 48 | $487.37 | $487.60 | $5,393.99 | $23,393.99 |
| Refinance, same remaining term | 8% / 48 | $439.43 | $439.60 | $3,092.81 | $21,092.81 |
| Refinance, extend the term | 8% / 60 | $364.98 | $364.65 | $3,898.47 | $21,898.47 |
Before refinance costs, the 48-month offer saves $2,301.18 in remaining interest versus keeping the loan. The 60-month offer saves $1,495.52 versus keeping it, but costs $805.66 more interest than the 48-month refinance and extends debt by a year. Its lower regular payment is a cash-flow benefit, not an extra saving.
Put fees in the right place
If the 48-month refinance above required a hypothetical $300 paid upfront, its total cash outlay from today would be $21,392.81 ($21,092.81 in loan payments plus $300), or $2,001.18 less than keeping the loan. The 60-month option with that same upfront fee would cost $22,198.47, saving $1,195.52 versus keeping it. Those are illustrative calculations, not fee quotes.
If a fee is financed instead, add it to the new principal and recalculate every payment and the interest; do not add the same fee again as upfront cash. Ask whether title or lien charges, origination costs, any prepayment penalty and optional products are paid now or added to the balance. APR can differ from the contract interest rate because certain charges affect the cost of credit. Use the lender's actual disclosures for that distinction.
Check your expected exit date
If you expect to sell, trade or pay off the car early, compare the cash paid and the remaining balance under each choice on that same date. Dividing an upfront fee by a lower monthly payment gives only a cash-flow recovery estimate; it cannot establish total savings when the loans amortize differently. Ask each lender for a payment schedule and payoff terms. Keep making the current payment until its servicer confirms the refinance payoff.
For a basic payment sensitivity check, Loanyzer's car loan calculator can help test an amount, rate and term. It is a purchase-loan planning tool, so use the written refinance quote to account for payoff timing, fees, APR and the old loan's remaining schedule. The CFPB also recommends comparing loan amount, APR, interest rate, term and total cost instead of deciding by payment alone.
