Diminished Value Claims Explained

A diminished value claim helps you recover the drop in value your car experiences after an accident. The diminished value can typically be collected from the insurer of the at-fault party and should be done any time you’re in an accident that you didn’t cause. Understanding how insurers calculate diminished value will help you negotiate to receive optimal compensation.

What is diminished value?

Diminished value—also known as diminution of value—is the difference in market price for a vehicle before and after an accident. It’s important to note that this is different from depreciation, which refers to a drop in value over time. Even if a car has quality repairs made with original manufacturer’s parts, the value of the car will be less than it was prior to the accident.

For instance, let's assume you’re selling a used car that was previously involved in an accident for $20,000. Furthermore, a buyer is willing to purchase your car until they discover that the car was in an accident, and then the buyer lowers their offer to $16,000. In this scenario the diminished value of your car is $4,000. In other words, your car is worth $4,000 less simply because it was involved an accident.

How to calculate diminished value

Most car insurance companies in the United States calculate diminished value using a formula called 17c. The name is derived from its use in a Georgia court case where the concept was first established. While there isn’t a diminished value calculator that'll be applicable in every instance, insurers typically use the 17c formula or a modified version of it. Below, we list the steps to calculate your vehicle’s diminished value estimate:

Step One: Check your car’s value. You can use the National Automobile Dealers Association’s (NADA) website to obtain an appraisal for your vehicle’s value. In order to get an accurate value, the website allows you to input specific information about your vehicle. Below, we list several vehicle options, features and details that will impact your car’s value.

Step Two: Calculate the base loss of value. Insurance companies commonly apply a 10% cap, also known as the base loss of value, to the sales value estimated by NADA. This simply means that the maximum amount for diminished value claims are 10% of the NADA appraisal.

Step Three: Apply a damage multiplier. Insurance companies use a damage multiplier to adjust the base loss of value from step two. In other words, the cap established above is multiplied by a number ranging from 0.00 to 1.00 to arrive at an adjusted figure for diminished value based on the insurer’s determination of damage. The figure that the base loss of value is multiplied by begins at 0.00 for cars with no structural damage or replaced panels, and can go as high as 1.00 for cars with severe structural damage.

1.00 - Severe structural damage

0.75 - Major damage to structure and panels

0.50 - Moderate damage to structure and panels

0.25 - Minor damage to structure and panels

0.00 - No structural damage or replaced panels

Step Four: Apply a mileage multiplier. The mileage multiplier functions the same way as the damage multiplier. The mileage multiplier reduces the—now adjusted—base loss of value depending on how many miles the vehicle has on its odometer. This means that an older car’s value will generally be lower than a newer car. The adjusted base loss of value from step three is multiplied by the appropriate mileage multiplier to arrive at the diminished value.

1.00 - 0-19,999 miles

0.80 - 20,000-39,999 miles

0.60 - 40,000-59,999 miles

0.40 - 60,000-79,999 miles

0.20 - 80,000-99,999 miles

0.00 - 100,000 miles or more

Example of a diminished value calculation

The first step in filing a diminished value claim is to go onto NADA’s website to get a sales value for your vehicle. If the NADA value for your vehicle is $20,000, then you calculate the base loss of value by using a 10% cap, which simply means multiplying $20,000 by 10%. The result of the calculation is $2,000 and serves as the highest amount a car insurer is willing to pay for a diminished value claim under formula 17c.

Insurance companies will use damage and mileage multipliers to adjust the base loss of value. In our case, let’s assume the insurer determines "major damage to structure and panels". This means that we multiply the $2,000 figure by 0.75 to receive an adjusted base loss of $1,500. The last step is to apply a mileage multiplier based on your car’s odometer reading. In this case, let’s assume the vehicle had an odometer reading of 62,000 miles. The damage multiplier would be 0.40. This damage multiplier of 0.40 would be multiplied by $1,500 to determine the final diminished value of $600. Below you can find an example of the calculations made to receive our final diminished value.

Formula: Value of Vehicle x 10% Cap x Damage Multiplier x Mileage Multiplier = Diminished Value

Step One: Check your car’s value. $20,000

Step Two: Calculate the base loss of value. $20,000 x 10% = $2,000

Step Three: Apply a damage multiplier. $2,000 x 0.75 = $1,500

Step Four: Apply a mileage multiplier. $1,500 x 0.40 = $600

Final Diminished Value $600

The problems of diminished value appraisal

While insurers commonly use the 17c formula to calculate a vehicle’s diminished value, it has many flaws that could result in lower diminished value appraisals than a car’s actual worth. The fair market value of a car is dependent on the features of the car itself, but can also depend on the location of the vehicle. Furthermore, the 10% cap placed by the 17c formula on the base loss of value is arbitrary. 10% was simply the precedent set under the original use of the 17c formula. Under the 17c formula, the amount of mileage on a car impacts the diminished value twice, once under NADA’s market value and again when assessing the mileage multiplier.

The key to negotiating a higher diminished value is to get appraisals and inspections by reputable third parties. Use websites other than NADA to supplement your vehicle’s fair market value. Websites—such as Kelley Blue Book—can present different results than NADA. Additionally, use a third party to obtain a physical inspection of the damage to your vehicle. A third party assessment of damage can be used to negotiate under step three of the 17c formula.

When and how to file a diminished value claim

You should file a diminished value claim any time you’re in a car accident where the other party is at-fault, so that you can recover your car’s decrease in value. Most insurance policies prohibit you from filing a diminished value claim against your own insurance company.

You should pursue a diminished value claim as soon as possible—ideally in the days following the accident—as states have statutes of limitations on property claims. While a state’s statute of limitations is usually measured in years, it's easier to provide supporting documents for your claim soon after the accident. Additionally, consider that you’ll want to provide an estimated market value for your car during the claims process and the value will decrease as time passes.

Every state has its own laws regarding diminished value and you can contact your state’s department of insurance to inquire about laws in your state. The following states have acknowledged the ability for a driver to recover diminished value from the at-fault party’s insurance company:

To file a diminished value claim you’ll need to contact the insurer of the at-fault party, also known as a filing a third-party claim. As previously mentioned, an appraisal from a third party can help your negotiations with the insurance company. Every insurance company will have its own process for diminished value claims. Be prepared to go to small claims court if the insurance company of the at-fault party refuses to acknowledge your diminished value claim.