The Prorated Refund Formula: How Cancellation Refunds Are Actually Calculated

If you cancel an extended warranty within the "free look" period — typically 30 to 60 days from purchase with no claims filed — you get a full refund. After that window, you get a prorated refund, and the math is rarely what people expect.

The basic formula

Most contracts use the lesser of two ratios: (1) time remaining on the contract divided by total contract term, or (2) miles remaining divided by total mileage allowance. Whichever fraction is smaller gets multiplied by the original contract price.

Fees and prior claims

Two things reduce that number: a cancellation fee (commonly $50 to $75 — sometimes higher) and any claims the administrator has paid on your behalf. If you used the warranty for a $1,800 repair last year, that $1,800 is subtracted from your refund. On older contracts where the repairs added up to more than the remaining prorated value, the refund can be zero.

A worked example

You paid $2,400 for a 6-year / 75,000-mile contract. After 2 years you've driven 20,000 miles. Time remaining: 4/6 = 66.7%. Miles remaining: 55,000/75,000 = 73.3%. The lesser ratio is 66.7%. 66.7% of $2,400 = $1,600. Subtract a $75 cancellation fee and a single $400 claim you filed last year. Refund: $1,125.

How to actually request the refund

Call the administrator (not the dealer who sold the contract) and request a cancellation form in writing. Submit the signed form by certified mail or via the customer portal, and include the current odometer reading — they will verify it. If the warranty was financed into your auto loan, the refund goes to the lender first to reduce the principal, not to you directly.

Shop floor: the math the F&I office hopes you skip

A regular of mine, a CPA named Carl, bought a five-year/100,000-mile VSC for his Tundra at the dealership and paid $2,890 for it financed into the loan. Eighteen months and 22,000 miles later he came in asking me to help him calculate the cancellation refund. He'd already used one covered claim — a $640 power steering rack — so he assumed the refund would be ugly. The dealership's F&I manager had quoted him "around $900" verbally, which felt low to Carl.

We sat down at the service desk and did the math together. The contract's prorated formula was the standard one: (unused term ÷ total term) × contract price, minus claims paid, minus a $75 cancellation fee. Time-based: he'd used 18 of 60 months = 30 percent used, so 70 percent remaining. Mileage-based: he'd used 22,000 of 100,000 miles = 22 percent used, so 78 percent remaining. The contract specified whichever method gave the customer the lower refund, which is annoyingly common — so time-based won, at 70 percent. That came out to $2,890 × 0.70 = $2,023. Subtract the $640 claim, subtract the $75 fee, and the actual refund was $1,308. Almost $400 higher than the F&I manager's "around $900" estimate.

Carl walked into the dealership the next day with the math written on a single sheet of paper, cited the contract section by number, and walked out with a check for $1,308 inside of a week. The F&I manager didn't argue once Carl produced the formula in writing. The lesson: dealerships often quote refunds low because they're guessing, or because they hope you'll accept the first number. Always do the math yourself, always reference the contract section, and always submit your cancellation request certified mail with a return receipt. Verbal quotes are worth exactly nothing.