Auto Payment Calculator with Tax and Trade

This auto payment calculator helps you determine your monthly payment including taxes and trade-in value. Simply enter your vehicle price, down payment, loan term, interest rate, sales tax rate, and trade-in value to get an accurate monthly payment estimate.

How to Use This Calculator

Using our auto payment calculator with tax and trade is simple:

Enter the purchase price of the vehicle
Enter your down payment amount
Select the loan term in months
Enter the annual interest rate
Enter the sales tax rate (as a percentage)
Enter the trade-in value of your current vehicle
Click "Calculate" to see your estimated monthly payment

The calculator will show you the total amount financed, the monthly payment including taxes, and the total interest paid over the life of the loan.

Formula Used

The monthly payment is calculated using the standard auto loan formula:

Monthly Payment = P × (r(1 + r)^n) / ((1 + r)^n - 1)

Where:

P = Principal loan amount (Purchase Price + Tax - Trade-in Value - Down Payment)
r = Monthly interest rate (Annual Rate / 12)
n = Number of payments (Loan Term in Months)

The total amount financed is calculated as:

Total Amount Financed = Purchase Price + (Purchase Price × Tax Rate) - Trade-in Value - Down Payment

Worked Example

Let's calculate the monthly payment for a $30,000 vehicle with:

Down payment: $3,000
Loan term: 60 months
Interest rate: 5% APR
Sales tax: 8%
Trade-in value: $2,000

First, calculate the total amount financed:

Total Amount Financed = $30,000 + ($30,000 × 0.08) - $2,000 - $3,000

= $30,000 + $2,400 - $2,000 - $3,000

= $27,400

Then calculate the monthly payment:

Monthly Payment = $27,400 × (0.004167(1 + 0.004167)^60) / ((1 + 0.004167)^60 - 1)

= $27,400 × 0.004545

= $124.20

So the estimated monthly payment would be $124.20.

Frequently Asked Questions

How does the trade-in value affect my monthly payment?

The trade-in value reduces the total amount you need to finance, which lowers your monthly payment. For example, trading in a $2,000 vehicle could save you $16.67 per month on a $30,000 loan over 60 months.

Is the sales tax included in the monthly payment?

Yes, the calculator includes the sales tax in the total amount financed, which affects your monthly payment. The tax is calculated as a percentage of the vehicle's purchase price.

Can I adjust the loan term to lower my monthly payment?

Yes, extending the loan term will generally reduce your monthly payment, but it will also increase the total interest paid over the life of the loan. Shorter loan terms typically have lower monthly payments but higher total interest costs.

What if I don't have a trade-in value?

Simply enter $0 for the trade-in value. The calculator will still include the sales tax in the total amount financed.

How accurate is this calculator?

This calculator provides an estimate based on the information you provide. Actual payments may vary slightly due to lender-specific calculations and additional fees.