Cash Back or Low Interest Calculator
Choose an option
How This Comparison Works
Dealers and manufacturers typically let you pick one incentive, not both: take a cash rebate up front and finance the rest at the "regular" dealer or bank rate, or skip the rebate and finance the full amount at a discounted promotional APR. This calculator assumes the cash rebate is applied as a reduction to the amount financed (not added to your down payment as extra cash), which is how most dealers structure the deal. It then runs a standard amortizing loan calculation for both scenarios over the same term and compares the total cost of each — the option with the lower total cost (monthly payment times number of months) wins.
Why Low APR Isn't Always the Winner
A 0% or 1.9% promotional rate sounds unbeatable, but it only saves you money on the interest you'd otherwise pay. If the cash rebate is large relative to the loan amount and term, taking the rebate and a higher rate can still cost less overall — especially on shorter loans where there isn't much time for interest to accumulate at either rate. As a rule of thumb, the rate gap matters more on longer terms and larger loan balances, while the rebate matters more on shorter terms and smaller balances.
Check the Math on Your Full Deal
Once you've picked an incentive, run the resulting loan amount, rate, and term through the auto loan calculator to see the complete payment breakdown, or use the loan calculator for a general amortization view if you're financing something other than a vehicle.
Frequently Asked Questions
How does this calculator decide which option is better?
It calculates the total cost (monthly payment times number of months) for both scenarios: financing the vehicle price minus your rebate at the regular APR, versus financing the full price at the discounted promotional APR with no rebate. Whichever scenario has the lower total cost is recommended.
Does the cash rebate get added to my down payment instead of reducing the loan?
This calculator assumes the rebate directly reduces the amount you finance, which is how most dealers structure the incentive. If your dealer instead lets you take the rebate as cash in hand while still financing the full price, you would enter the loan amount and rate manually using the auto loan calculator instead.