Estimate your monthly payment, including trade-in and sales tax
💡 Why This Matters Your monthly payment depends on more than just the sticker price — trade-in value and sales tax both change how much you actually finance. This calculator factors in both, so you get a realistic number before you're at the dealership.
In most states, trading in your old car doesn't just save you a step — it can also lower the sales tax you owe, since tax is often calculated on the price after your trade-in is subtracted.
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This calculator starts with the vehicle's price, subtracts your trade-in value and down payment to find the taxable amount, adds sales tax on that reduced amount (the standard method in most states), then finances the result using the standard loan amortization formula based on your APR and loan term.
The monthly payment reflects principal and interest only — it's what you'd pay the lender each month, not including registration fees, insurance, or dealer add-ons. The total cost figure shows what you'll pay over the life of the loan, including all interest.
Sales tax treatment of trade-ins varies by state — some states tax the full price regardless of trade-in, so double-check your local rules before finalizing a budget. This also doesn't account for registration, title fees, dealer documentation fees, or extended warranties, which can add hundreds or thousands to your total.
Use this earlier in your car-buying process than a standard auto loan calculator — while you're still deciding on trade-in value, down payment, or negotiating price — rather than after you already know your exact loan amount. Compare a few price/trade-in/down-payment combinations to see what actually fits your budget.
Example: A $30,000 car with a $5,000 trade-in and $2,000 down payment. Taxable amount: 30,000 − 5,000 − 2,000 = $23,000. At 7% sales tax, that adds $1,610. Financing $24,610 at 6.5% APR over 60 months gives a payment of about $481/month.
This calculator factors in your trade-in value and sales tax to estimate what you'll actually finance — useful earlier in the car-buying process, before you know your exact loan amount.
In many states, yes — sales tax is calculated on the price after subtracting trade-in value. Rules vary by state, so check your local DMV for the exact treatment.
Just leave trade-in value at 0. The calculator will use the full purchase price minus your down payment as the amount financed.