Real data
Where the 17c diminished value formula comes from
The 17c formula is not science — it is a courtroom shortcut. It comes from State Farm Mutual Automobile Ins. Co. v. Mabry, a 2001 Georgia Supreme Court case where 25,000+ drivers claimed lost resale value after repairs. To handle the class at scale, the court adopted a generic formula capped at 10% of the car's value. Insurers now apply it as a default — which is exactly why first offers are often low.
Source: State Farm Mut. Auto. Ins. Co. v. Mabry, Supreme Court of Georgia (2001). The 17c formula is an insurer estimate, not a binding valuation, and first offers are frequently below a car's true lost value — use the calculator above and consider an independent appraisal.
The method
How the 17c diminished value formula works
Start from 10% of your car's value, then apply a damage multiplier and a mileage multiplier.
Base value cap
Start with 10% of your car's pre-accident market value (KBB/NADA).
Damage multiplier
0.00–1.00 for severity — structural damage scores high.
Mileage multiplier
Higher mileage means less diminished value.
Estimated DV
Cap × damage × mileage = your claim estimate.
Appraisal
An independent appraisal supports a higher figure if the insurer lowballs.
Adjust for your state
Diminished value by state
Eligibility and how insurers handle 17c vary by state — check before you file.
Case law clearly supports diminished value, e.g. Georgia.
Third-party DV claims are accepted but insurers push back; an appraisal helps.
Some states limit recovery or first-party DV; check before filing.
Insurers recognize 17c but are not bound by it; negotiation matters.
See the state-specific calculator and average data:
Questions
Diminished value claim FAQ
A standard method: 10% of pre-accident value × a damage multiplier × a mileage multiplier. It is an estimate insurers recognize, not a guaranteed payout.
Often yes — from the at-fault driver's insurer, because a repaired car with an accident history still sells for less.
Usually it is a third-party claim against the at-fault driver; first-party claims depend on your policy and state.
Pre-accident value (KBB/NADA), repair invoices, and an independent appraisal if needed.
Newer, higher-value, low-mileage cars with structural or frame damage lose the most.
Get your personalized estimate
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