Diminished Value Calculator

What Is Diminished Value?

Diminished value is the loss in your vehicle's market value after it has been involved in an accident — even after it has been professionally repaired. When you go to sell or trade in your car, the accident history will reduce what buyers are willing to pay. This difference between your car's pre-accident value and its post-repair value is called diminished value.

How the 17C Formula Works

The 17C formula, established in the Georgia lawsuit Mabry v State Farm, is the standard method insurance companies use to calculate diminished value. Here's the step-by-step breakdown:

• Step 1: Determine your vehicle's pre-accident market value (Kelley Blue Book, NADA, or local market)
• Step 2: Apply a 10% cap — This is the maximum base loss insurance companies will consider
• Step 3: Apply a damage multiplier (0.00 to 1.00) based on structural damage severity
• Step 4: Apply a mileage multiplier (0.00 to 1.00) based on current odometer reading
• Step 5: (Advanced) Adjust for prior accident history

Damage Multiplier Guide

• 1.00 — Severe structural damage: Frame damage, unibody damage, or major structural components compromised
• 0.75 — Major damage: Extensive damage to structure and panels, requiring significant repair
• 0.50 — Moderate damage: Moderate structural and panel damage
• 0.25 — Minor damage: Light structural or panel damage, no frame issues
• 0.00 — No structural damage: Cosmetic only, replaced panels, no structural impact

Mileage Multiplier Guide

• 1.00: 0 – 19,999 miles — Excellent
• 0.80: 20,000 – 39,999 miles — Good
• 0.60: 40,000 – 59,999 miles — Average
• 0.40: 60,000 – 79,999 miles — Fair
• 0.20: 80,000 – 99,999 miles — High mileage
• 0.00: 100,000+ miles — Very high mileage

Types of Diminished Value

• Inherent Diminished Value: The most common type — loss due to accident history, even after perfect repairs. This is what the 17C formula calculates.
• Immediate Diminished Value: The car's value immediately after the accident, before repairs. Rarely used by insurance companies.
• Repair-Related Diminished Value: Additional loss from poor repairs, aftermarket parts, or substandard workmanship.

How to File a Diminished Value Claim

• Check eligibility: File with the at-fault driver's insurance, not your own (unless they're uninsured)
• Calculate your value: Use this calculator and document your vehicle's pre-accident worth
• Gather evidence: Take photos of damage, get repair estimates, and document all communications
• Consider a third-party appraisal: Professional appraisals can strengthen your claim
• Submit a formal demand letter: Include your calculation, evidence, and a request for payment
• Be persistent: Insurance companies may deny initially — negotiate or seek legal advice

Frequently Asked Questions

• Can I claim diminished value if I was at fault? — Generally no, unless you have a specific rider in your policy. Most states require the other driver to be at fault.
• How long do I have to file a claim? — Statute of limitations varies by state, typically 2-4 years from the accident date.
• Does my state require diminished value payments? — Most states allow diminished value claims, but Georgia is the only state with a clear statutory requirement. Check local laws.
• What if my car is a lease? — You can still claim diminished value, but payment goes to the leasing company or directly to you depending on the lease terms.
• Will my insurance rates increase? — Filing a diminished value claim against the at-fault driver's insurance should not affect your rates.