Auto Refinance Calculator

Q: When should I refinance my auto loan?

Refinancing makes sense when you can get a rate at least 1-2% lower than your current rate, you have 12+ months remaining on your loan, and you are not underwater. Common triggers: your credit score improved, market rates dropped, or you originally got a high rate from a dealer.

Q: Does auto refinancing cost anything?

Most auto refinance lenders charge $0 in fees, unlike mortgage refinancing which can cost thousands. Some states charge a re-titling fee ($5-$75) and a few charge sales tax on the refinanced amount. Early payoff penalties on auto loans are rare.

Q: What are the requirements to refinance an auto loan?

Typical requirements: the loan is at least 12 months old, your vehicle is less than 10 years old with under 100,000-150,000 miles, the loan-to-value ratio is under 125%, and your balance is at least $5,000-$7,500. Credit unions often have more flexible requirements.

Q: Will refinancing hurt my credit score?

Rate shopping for auto refinancing within a 14-day window counts as a single hard inquiry, typically dropping your score by 5-10 points temporarily. The score usually recovers within a few months. Lower payments and reduced debt can help your score long-term.

Q: Should I extend the loan term when refinancing?

Extending the term lowers your monthly payment but increases total interest paid. If your goal is to save money overall, keep the same or shorter term. Adding extra payments can offset a longer term and still save you money.

Should you refinance your auto loan? Compare your current loan to a refinanced loan, get a personalized recommendation based on your credit and vehicle, and see how extra payments can save you even more.

Compare your current auto loan to a refinanced loan

Current loan balance

Remaining principal on your auto loan

Current interest rate

APR on your current auto loan

Remaining term (months)

Months left on your current loan

New interest rate

Rate offered by the new lender

New term (months)

Length of the new loan

Refinance fees

Most auto refi lenders charge $0

Sales tax on refi

Some states charge sales tax on refinanced amount

Payoff penalty on current loan

Early payoff penalty (most auto loans have none)

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How to Use This Calculator

Refinance Savings tab

The default tab. Enter your current loan balance, current interest rate, remaining months, and the new rate and term being offered. The calculator compares your current payment path to the refinanced loan and shows monthly savings, total interest savings, and a full cost comparison. Expand "More options" to add refinance fees, sales tax, or payoff penalties.

Should I Refinance? tab

Not sure if refinancing is worth the effort? Enter your loan details and credit score tier. The calculator estimates the rate you can qualify for, scores your situation from 1 to 10, and gives a clear recommendation based on rate improvement potential, remaining term, vehicle age, loan-to-value ratio, and mileage.

Refinance + Extra Payment tab

See the combined power of refinancing and making extra payments. Enter your refinanced loan details plus an extra monthly amount. The calculator shows how many months early you can pay off the loan, interest saved from refinancing alone, interest saved from extra payments, and the combined total savings.

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The Formula

Auto loan payments use the standard amortization formula. Refinancing saves money when the new rate produces a lower total interest cost.

PMT = P × r × (1+r)ⁿ / ((1+r)ⁿ - 1)

Where:
P = loan principal (balance)
r = monthly interest rate (annual rate ÷ 12)
n = number of monthly payments

Total Interest = (PMT × n) - P
Interest Savings = Current Total Interest - New Total Interest

For extra payments, each additional dollar goes directly to principal, reducing the balance faster and shortening the loan. The interest saved compounds because every month after the extra payment, the balance is lower, so less interest accrues.

Example

Maria — Marketing Associate, 29, Austin TX

Maria has a $22,000 auto loan at 8.5% with 48 months remaining. Her current payment is $542/month. After improving her credit score to 710, she refinances to 6.5% for 48 months. She also decides to add $100/month in extra payments.

Refinance Savings tab

Current monthly payment$542

New monthly payment$522

Monthly savings$20

Total interest (current)$4,016

Total interest (new)$3,056

Total interest savings$960

Refinancing alone saves Maria $960 in interest with $0 in fees. Her monthly payment drops by $20.

Refinance + Extra Payment tab

Base payment (after refi)$522

With $100/mo extra$622

Payoff without extra48 months

Payoff with extra39 months

Interest saved from extra$580

Combined savings$1,540

By adding $100/month extra, Maria pays off in 39 months (9 months early), saving an additional $580 in interest. Combined savings from refinancing and extra payments: $1,540.

Auto Refinance Rates by Credit Tier (March 2026)

Estimated auto refinance rates based on credit score. Actual rates vary by lender, vehicle age, loan amount, and term length.

Excellent (720+)5.0% – 5.9%

Good (680–719)6.0% – 7.5%

Fair (640–679)8.0% – 11.0%

Poor (<640)12.0% – 18.0%

Sources: Bankrate, myAutoloan, Edmunds (March 2026). Average auto loan rate: 7.1% new, 11.3% used.

FAQ

When should I refinance my auto loan? ▼

Refinancing makes sense when you can get a rate at least 1-2% lower than your current rate, you have 12+ months remaining on your loan, and you are not underwater (owe more than the car is worth). Common triggers: your credit score improved since you got the loan, market rates dropped, or you originally got a high rate from a dealer.

Does auto refinancing cost anything? ▼

Most auto refinance lenders charge $0 in fees, unlike mortgage refinancing which can cost thousands. Some states charge a re-titling fee ($5-$75) and a few charge sales tax on the refinanced amount. Check your current loan for early payoff penalties, though these are rare for auto loans.

What are the requirements to refinance an auto loan? ▼

Typical requirements: the loan is at least 12 months old, your vehicle is less than 10 years old with under 100,000-150,000 miles, the loan-to-value ratio is under 125%, and your balance is at least $5,000-$7,500. Credit unions often have more flexible requirements than banks or online lenders.

Will refinancing hurt my credit score? ▼

Rate shopping for auto refinancing within a 14-day window counts as a single hard inquiry on your credit report, typically dropping your score by 5-10 points temporarily. The score usually recovers within a few months. The long-term benefit of lower payments and reduced debt can actually help your score.

Should I extend the loan term when refinancing? ▼

Extending the term lowers your monthly payment but increases total interest paid. If your goal is to lower monthly costs, a longer term can help. If your goal is to save money overall, keep the same or shorter term. Use the Refinance + Extra Payment tab to see how adding extra payments can offset a longer term.

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