What diminished value is
Diminished value is the drop in a car's resale value after an accident, even when the repair is good, because the accident now shows on its history. Buyers pay less for a car with an accident history than for the same car with a clean one. A diminished value claim asks for that difference. The calculator above estimates it as a screening range, not an appraisal.
How the 17c formula works
Many insurers start from the 17c formula: the pre-accident value, times 10%, times a damage modifier from 0 to 1, times a mileage modifier from 0 to 1. On a $30,000 car with moderate damage and 45,000 miles, the published worksheet gives $900 and State Farm's linear mileage method gives $825. A car with replaced panels but no structural damage, or with 100,000 miles or more (150,000 for some vehicles), gets $0. No statute requires it, and you can dispute the number. Our 17c formula guide shows every multiplier.
Who pays diminished value
Usually the at-fault driver's insurer. Of the 51 jurisdictions we track (50 states and DC), our research found diminished value recoverable from the at-fault driver in 31, limited in 6, not recoverable in North Dakota and unsettled in 13.
Your own policy usually does not pay it. Our state research found it may be recoverable on your own policy only in Georgia, Oregon and Washington, and only under some policy wording. In Oregon, the court ruled on a repair that did not restore the car’s pre-loss physical condition, and did not decide a claim for stigma alone after a full repair. In 24 jurisdictions the rule is unclear. Vermont is one: a state bulletin says insurers must review these claims unless the policy says otherwise, but it does not promise payment. The diminished value laws by state page compares every state, and our guide on how to file a diminished value claim covers evidence and the demand letter. The Diminished Value Claim Kit ($49, not on sale yet) will draft that letter from your numbers, with a 30-day refund.