Knowledge Hub · Buying & ownership · Expert guide · 7 min read

Cash rebate or 0% APR? Run the math before you pick

$3,000 cash back or 0% for 60 months? A one-line rule, a worked example with real payments, and the traps that flip the answer, so you pick the one that saves more.

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Manufacturer offers often come as an either/or: take $3,000 cash back, or take 0% financing for 60 months. Most buyers pick whichever sounds bigger, and the dealership is happy either way, because the manufacturer pays for both. But the two can be thousands of dollars apart, and the right answer depends on numbers you already have: the price, how much you finance, for how long, and what rate you could get elsewhere.

Here’s the core of it: the rebate cuts what you borrow, while 0% cuts what borrowing costs. If you can get a low enough rate from your own bank or credit union, the rebate plus outside financing usually wins; if outside rates are high, 0% often does. Below: the one-line rule, a worked example with real payments, where the answer flips, what else changes it, the dealership’s angle, a quick worksheet and what to say.

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In the full guide

  1. How the two offers work
  2. The one-line rule
  3. Worked example: $3,000 cash or 0% for 60 months
  4. Where the answer flips
  5. Other things that change the answer
  6. The dealership’s angle
  7. Quick worksheet
  8. What to say
  9. Your game plan

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