Diminished value (değer kaybı) after a Turkish traffic accident: the claim insurers hope you will not make.

1. What Diminished Value Actually Is

Turkish practice calls it araç değer kaybı — the reduction in a vehicle's market value that persists after a proper repair, because the vehicle now carries a recorded damage history. It is a distinct head of loss from the repair itself. The bodyshop invoice restores the car; it does not restore the price a buyer will pay for it.

Three points about the nature of the claim decide most disputes:

• It is property damage, not injury. It belongs to the same claim as the repair cost, and it is asserted against the same insurer, but it is calculated separately and is frequently omitted from the first settlement offer.
• It attaches to the vehicle, not to the driver. The owner of the damaged vehicle is the claimant, whether or not the owner was driving at the time.
• It requires an accident record. The loss arises because the damage becomes visible to a future buyer — through the traffic accident report, the insurance claim history, and the repair record. Damage that leaves no trace and no record produces no diminished value.

Foreign owners are affected disproportionately, because a vehicle that has to be sold on departure is sold into exactly the market that prices the accident history most harshly.

2. Who Pays: The Compulsory Liability Insurer

Turkish motor insurance has two layers, and confusing them is the most common reason a diminished value claim goes nowhere.

• Compulsory motor third-party liability insurance (Zorunlu Mali Sorumluluk Sigortası, ZMSS or "trafik sigortası") is carried by every registered vehicle and covers the damage that vehicle causes to others. A diminished value claim is made against the at-fault vehicle's ZMSS insurer.
• Own-damage cover (kasko) is voluntary and covers your own vehicle. It is not the natural home of a diminished value claim, because the loss you are claiming is a loss caused to you by another party.

Two structural limits follow. First, the ZMSS is a policy with limits, and the compulsory cover responds only up to the sums insured for material damage; where fault is shared, the recovery is reduced in proportion to the other driver's share of fault. Second, the insurer's exposure is defined by the policy and its General Conditions, which is why the claim is assessed against a published framework rather than negotiated at large.

Article 99 of the Highway Traffic Act (KTK No. 2918) sets the payment clock once the file is complete: insurers must pay the amounts falling within the compulsory liability limits to the entitled party within eight business days from the date the documents specified in the compulsory motor liability general conditions are delivered to the insurer's head office or one of its units. That eight-day period is a useful lever, and it only starts running when the specified documents have actually been delivered — which is a reason to send a complete file rather than a partial one.

3. The Mandatory Written Application (KTK 97)

This is the step foreign claimants most often skip, and skipping it is fatal to the proceedings rather than merely inconvenient.

Article 97 of the KTK, as amended in 2016, provides that the injured party must make a written application to the relevant insurance undertaking before going to court within the limits provided for in the compulsory motor liability insurance. If the insurance undertaking does not answer the application in writing within fifteen days at the latest from the date of application, or if there is a dispute that the answer given does not meet the claim, the injured party may file a lawsuit or apply to arbitration within the framework of Law No. 5684.

Three consequences follow directly from that wording:

1. The application must be written. A telephone call to the claims line does not start the clock, and cannot later be proved.
2. Fifteen days of silence is enough. You do not need a rejection letter to proceed; the absence of a written answer within the period opens the route to court or arbitration by itself.
3. A partial or inadequate answer also opens the route. The provision covers the situation where an answer is given but does not meet the claim — the typical response being an offer that covers repair costs and ignores diminished value entirely.

Keep proof of the application and of its date. That single document is what establishes both the admissibility of the claim and the start of the eight-business-day payment period under Article 99.

4. How the Figure Is Built

Diminished value is not a percentage anyone is free to invent. The calculation framework sits in the General Conditions of Compulsory Motor Third-Party Liability Insurance and its annex, issued under the insurance regulatory framework rather than in the Highway Traffic Act itself. The General Conditions are amended from time to time, and the version in force on the date of the accident governs — so the first question an experienced adviser asks is the accident date, not the make of the car.

What the framework does, in substance, is convert a set of objective inputs into a figure:

• The vehicle's market value immediately before the accident, which anchors everything else.
• Age and recorded mileage, both of which reduce the marginal effect of a damage record.
• The nature and location of the damage — structural and chassis-adjacent repairs weigh far more heavily than a replaced bumper or a repainted wing.
• Prior damage history, because a vehicle that already carried a record loses less additional value from the new one.

In practice the figure is produced by a licensed loss adjuster (sigorta eksperi) or, in contested files, by a court- or arbitration-appointed expert. Reports that simply assert a percentage of the vehicle's value, without applying the framework to the actual repair scope, are routinely discounted.

Certain claims fail on the merits regardless of the arithmetic: total losses written off rather than repaired, vehicles whose repair was not carried out to a documented standard, and cases where the claimant's own share of fault reduces or eliminates the recoverable amount.

5. Deadlines and Prescription (KTK 109)

Article 109 of the KTK governs limitation, and its wording repays close reading because the two periods run on different triggers. Claims for compensation of material damage arising from motor vehicle accidents become time-barred (zamanaşımına uğrar) after two years from the date on which the injured party learned of the damage and of the person liable to compensate, and in any event after ten years from the date of the accident.

Three further rules in the same article matter in real files:

• The criminal extension. If the claim arises from an act requiring criminal punishment and the criminal law prescribes a longer limitation period for that act, that longer period applies to claims for material compensation as well. In accidents involving injury or death, this frequently rescues a claim that would otherwise have expired.
• Interruption works both ways. If prescription is interrupted against the person liable to compensate, it is also interrupted against the insurer; and prescription interrupted as regards the insurer is deemed interrupted as regards the person liable as well.
• Recourse between liable parties is subject to its own two-year period, running from when the party fully performed its own obligation and learned of the person against whom recourse is to be taken.

Note the statutory verb: the article says the claims become time-barred. This is prescription, not a forfeiture period — it can be interrupted, and it must be raised by the other side rather than applied by the court of its own motion. That distinction is worth preserving in correspondence, because insurers occasionally describe the two-year period as though it extinguished the right automatically.

6. Arbitration or Court? A Comparison

Once the Article 97 application has been made and either fifteen days have passed without a written answer or the answer does not meet the claim, the claimant chooses between the ordinary courts and the Insurance Arbitration Commission established under the Insurance Act (Law No. 5684).

Article 30 of Law No. 5684 sets the entry condition in terms that mirror KTK 97: to apply to the Commission, the person in dispute with the insurance undertaking must have made the necessary applications to that undertaking and have documented that the claim was concluded negatively in whole or in part; the undertaking's failure to answer in writing within fifteen business days of the application date is also sufficient. The same article closes one door explicitly: no application may be made to the Commission in relation to disputes that have already been brought before a court.

For a straightforward diminished value dispute — liability admitted, repair documented, only the figure in issue — the arbitration route is usually faster and proportionate to the amount at stake. Where fault is contested, or where the property claim sits alongside an injury claim, keeping the whole dispute in one forum is generally the better call.

7. Evidence, Sequence and Common Failures

The file that recovers is the file that was assembled before the first letter went out. In practical order:

1. The accident report. The official traffic accident report or the agreed statement completed at the scene, which establishes the parties, the vehicles and the fault position.
2. Proof of ownership at the date of the accident — the claim belongs to the owner.
3. The repair documentation. Invoices, the parts list distinguishing replaced from repaired panels, and photographs before and after. The scope of repair drives the valuation.
4. Vehicle data. Registration details, age, and recorded mileage at the time of the accident.
5. An appraisal applying the General Conditions framework in force on the accident date.
6. The written application to the insurer under KTK 97, with proof of delivery and date.

Claims fail for a small and repetitive set of reasons. The application to the insurer was never made in writing, so the file is inadmissible. The two-year period under KTK 109 expired while the owner waited for the bodyshop and the insurer to finish arguing about the repair. The claimant sued in court and then tried to move to arbitration, which Article 30 forecloses. Or the appraisal asserted a round percentage instead of working through the framework, and the expert appointed by the tribunal produced a materially lower figure that the claimant had no basis to challenge.

None of these is a problem of Turkish law being unfavourable to the claimant. Each is a sequencing problem, and each is avoidable at the outset of a claim that, in a vehicle of any real value, is usually worth considerably more than owners assume.

Scope. This page is general information about Turkish law and procedure. It is not legal advice, it is not an assessment of your situation, and reading it does not create a lawyer-client relationship. Statutory figures, thresholds and rates are revised periodically — check the current position before relying on any of them. Any particular case turns on its own documents and facts.