DiminishValueClaim

Practical guide · Reviewed July 17, 2026

How to file a diminished value claim

Short answer

Identify who caused the loss, finish and document the repairs, measure the remaining market loss, and send a written demand to the correct claim handler. Do not start with a generic percentage or wait for the insurer to volunteer payment.

Start with the correct claim

Most claims are third-party property-damage claims against the at-fault driver. Ordinary collision coverage with your own insurer is a different contract question. UIM or UMPD coverage may use the damages you could recover from an uninsured driver.

Wait for the right repair record

Inherent diminished value is usually measured after proper repairs. Save the first estimate, every supplement, the final invoice, calibration records, parts information, and photos. If the vehicle is a total loss, the dispute is normally actual cash value—not diminished value.

Measure the actual vehicle

Build the pre-loss value from accurate trim, options, mileage, condition, geography, and history. Then compare similar vehicles with accident histories. A credible appraisal explains its data, adjustments, and limitations.

Send a focused demand

State the amount, short factual basis, and enclosed evidence. Ask for a written response and the insurer’s calculation if it disagrees. Avoid invented deadlines or threats. Keep proof of delivery and a dated communication log.

Protect the deadline

The filing deadline depends on the jurisdiction and claim. Negotiation and insurance-department complaints usually do not pause it. Confirm the current statute and who must be sued before time becomes short.

Research sources