A diminution in value claim is made to protect a vehicle’s market value after it has been damaged, ensuring the owner does not suffer a loss when selling the vehicle. The claim for diminished value should be submitted to the insurer of the at-fault party.
The insurance company is required to respond to the vehicle owner. If the insurer fails to respond, the vehicle owner has the right to file a diminished value lawsuit.
What Documents Are Required for a Diminished Value Claim?
Required documents for a diminished value claim include the following:
- An accident report (kaza tespit tutanağı) is required.
- Repair shop reports and invoices obtained from the service are requested.
- An expert appraisal report obtained after the accident is needed.
- The insurance policy must be presented.
- If there are witnesses, a list indicating those who will testify during the case is requested.
- Documentation such as photographs of the vehicles after the accident is required.
Where Should a Diminished Value Claim Be Filed?
A diminished value claim should be filed with the insurance company of the party found at fault in the accident. You must submit the claim to the at-fault driver’s compulsory motor insurance provider.
If the insurance company responds negatively or fails to respond to the diminished value claim, the Insurance Arbitration Commission should be contacted.
If the at-fault driver is uninsured, the vehicle owner may file suit directly against the driver or the vehicle’s registered owner. When the responsible party cannot be identified, claims are typically pursued through the insured parties’ channels.
What Is the Statute of Limitations for a Diminished Value Claim?
The time limit to file a diminished value claim is two years. If a vehicle has suffered damage not caused by its owner, the owner must file a diminished value claim within two years after identifying the at-fault party.
For example, if the at-fault party fled the scene, the two-year limitation period begins once the fleeing driver is identified.
How Is Diminished Value Calculated?
Key factors considered in calculating diminished value include:
- The vehicle’s damage history.
- Mileage, make, model and year of manufacture are taken into account.
- The vehicle’s first registration or road-entry date.
- Which parts were affected during the damage event.
- Parts used during repairs and whether original or aftermarket parts were fitted.
- The vehicle’s second-hand market value is considered when calculating the loss in value.
When and in Which Court Is a Vehicle Diminished Value Lawsuit Filed?
The purpose of filing a diminished value lawsuit is to obtain payment for the vehicle’s loss in value. If the at-fault party fled, the at-fault party is uninsured, or the insurer did not respond to the diminished value claim, a lawsuit should be filed to recover the loss.
If the defendant is only the insured individual, the case should be brought before the Civil Court of First Instance. If both the insurance company and the insured party are listed as defendants, the lawsuit should be filed with the Commercial Court of First Instance.

How Long Does a Vehicle Diminished Value Lawsuit Take to Conclude?
The typical duration of a diminished value lawsuit is about 4–8 months. While the insurer’s review and response times vary, if the insurance company has not addressed the matter, a lawsuit should be filed. Factors that can extend the length of the case include:
- The judicial process during litigation can prolong the case.
- Notification and service of the complaint to the parties may take a long time.
- The expert report may take longer than anticipated to be issued.
- Objections to submitted reports and any need for re-examination by an expert can delay the outcome.
- If the diminished value case coincides with the court’s recess (judicial holiday), the resolution may take longer.