What Uninsured Motorist Arbitration Is and When You Use It
Uninsured motorist arbitration is a process to resolve a dispute between you and your own insurance company about how much your uninsured motorist (UM) claim is worth. You use it when the other driver has no insurance, you have UM coverage, your insurer has made you an offer you disagree with, and you want a neutral third party to decide the value instead of going to court.
California law requires insurers to include this option in UM policies. It is faster and cheaper than a lawsuit, and you do not need a lawyer to participate, though many people bring one. The arbitrator's decision is binding on both you and the insurance company — meaning neither side can appeal it to a judge afterward.
You can only use arbitration if your insurer has already denied your claim or offered you a settlement amount you reject. You cannot file for arbitration before that conversation happens.
Key Takeaways
- Arbitration is available only after your insurer makes an offer or denies your claim, and you must request it in writing within the timeframe your policy allows.
- California law sets the process: you and your insurer each pick an arbitrator, those two arbitrators pick a third, and the three decide your claim's value together.
- You will need medical records, repair estimates, lost wage documentation, and proof of the other driver's lack of insurance to present your case.
- The arbitration hearing usually takes one day, and you receive a decision within 30 days of the hearing ending.
- You can represent yourself or hire an attorney; many people hire one because the process involves presenting evidence and arguments about damages.
How to Request Arbitration in Writing
Your first step is to send your insurance company a written request for arbitration. California law does not require a specific form, but your policy documents will state the address where you must send it and any important date for making the request. Read your policy's UM section carefully — important date vary by insurer and typically range from 30 to 60 days after the insurer's denial or final settlement offer.
Your letter should state clearly that you are requesting uninsured motorist arbitration under California Insurance Code Section 11580.2. Include your policy number, the date of the accident, the claim number if one was assigned, and a brief statement that you disagree with the insurer's valuation of your claim. You do not need to argue your case in this letter — that comes later. Send it by certified mail with return receipt so you have proof the company received it.
Once the insurer receives your request, they must respond within 30 days and confirm they accept arbitration. If they do not respond, California law treats their silence as acceptance. Keep copies of everything you send and receive.
Understanding the Three-Arbitrator Process
California requires a three-arbitrator panel for UM disputes. Here is how it works: you pick one arbitrator, your insurance company picks one arbitrator, and those two arbitrators together pick a third arbitrator to serve as the neutral chair. Each side pays for the arbitrator they choose; the cost of the neutral arbitrator is split between you and the insurer.
The insurer will send you a list of available arbitrators along with their backgrounds, experience, and hourly rates. You will do the same — the insurer will receive a list and can strike names they object to. You are looking for someone with experience in personal injury or insurance disputes, not necessarily a lawyer. Many retired judges, mediators, and claims professionals serve as arbitrators.
Once all three arbitrators are seated, the neutral arbitrator (the chair) will set a hearing date, usually within 60 to 90 days. The chair also sets the rules for how evidence will be presented and what documents must be exchanged beforehand.
Gathering and Organizing Your Evidence
You will need to collect and present evidence to prove the value of your claim. This includes medical records from every provider who treated you after the accident — hospital records, doctor's notes, physical therapy records, and any imaging or test results. If you saw a mental health provider for accident-related trauma, include those records too.
Bring repair estimates or an actual repair bill if your vehicle was damaged. If the vehicle was totaled, bring the insurance company's valuation report or independent appraisals showing the vehicle's pre-accident value. Gather documentation of any lost wages — pay stubs, a letter from your employer stating the dates you missed work, and your hourly rate or salary.
Obtain proof that the other driver was uninsured. This is usually a police report stating no insurance was found, or a declaration from your own insurer confirming they could not locate coverage on the at-fault vehicle. You will also need the accident report itself, photos of vehicle damage, and any witness statements.
Organize all documents in chronological order and make three copies — one for yourself, one for your arbitrator, and one for the insurer's arbitrator. The neutral arbitrator will receive copies from both sides.
What Happens at the Arbitration Hearing
The hearing is informal compared to a court trial, but it follows a structure. You or your attorney will present your case first, explaining your injuries, the treatment you received, your expenses, and how the accident affected your life and work. You will present your documents and may testify under oath. The insurer's representative will do the same, presenting their valuation and arguing why your damages claim is too high.
You will have the chance to ask questions of the insurer's representative and to respond to their arguments. The arbitrators may ask you questions about your medical treatment, your lost wages, or your damages. This is not a formal cross-examination like in court — the tone is usually more conversational, though the stakes are real.
Hearings typically last one day, though complex cases may take longer. You do not need to prove your case "beyond a reasonable doubt" like in criminal court. Instead, the arbitrators decide based on the preponderance of the evidence — meaning what is more likely true than not.
The Decision and What Comes After
The three arbitrators will meet privately after the hearing to discuss and vote on the value of your claim. California law requires them to issue a written decision within 30 days of the hearing ending. The decision will state the amount they have awarded you and a brief explanation of their reasoning.
Once you receive the decision, the insurer must pay the awarded amount within a set timeframe — usually 30 days. If the insurer does not pay, you can file a motion to enforce the arbitration award in court, though this is rare.
The arbitration award is final and binding. You cannot appeal it to a judge or ask for a new hearing if you disagree with the amount. The same is true for the insurer — they cannot challenge the award either. This finality is one reason arbitration is faster than litigation, but it also means you should prepare your case carefully and consider hiring an attorney if your damages are substantial.
When to Hire an Attorney for Arbitration
You have the right to represent yourself in arbitration, and many people do, especially if their injuries and damages are minor. However, arbitration involves presenting evidence, making legal arguments about what damages are recoverable, and cross-examining the insurer's position. An attorney can help you value your claim accurately, organize your evidence, and present it persuasively.
Many personal injury attorneys work on a contingency basis for arbitration cases, meaning they take a percentage of your award rather than charging an hourly fee. This arrangement aligns their incentive with yours — they earn more if you win more. Before hiring an attorney, ask about their experience with UM arbitration in California and what percentage they charge.
If your medical bills are under $5,000 and you have no lost wages, you may be comfortable handling arbitration yourself. If your bills exceed $10,000, you have ongoing treatment, or you lost significant work time, an attorney is usually worth the cost.
Frequently Asked Questions
Can I file for arbitration if the other driver was partially at fault?
Yes. Arbitration is about the value of your claim, not about who was at fault. California's comparative negligence rules still explore — if you were 20% at fault, your award will be reduced by 20%. The arbitrators will consider fault as part of their decision, but fault does not prevent you from using arbitration.
What if I settle with the insurer before the arbitration hearing?
You can settle at any time, even after requesting arbitration. If you and the insurer reach an agreement on the claim's value before the hearing date, you can withdraw your arbitration request in writing. The settlement becomes final once both parties sign the settlement agreement.
How much does arbitration cost?
You pay for the arbitrator you select, and the insurer pays for theirs. The neutral arbitrator's fee is split 50/50. Arbitrator fees typically range from $300 to $500 per hour, and a one-day hearing usually costs $2,000 to $4,000 total per side. Your insurer may argue you should pay their arbitrator's fee if you lose, but California law generally prohibits this.
What if the arbitrators cannot agree on a value?
California law requires the three arbitrators to reach a single decision. If the two arbitrators you and the insurer each selected cannot agree, the neutral arbitrator breaks the tie. A majority vote (two out of three arbitrators) is binding.
Can I appeal the arbitration decision?
No. Arbitration awards are final and binding in California. You cannot appeal to a judge or request a new hearing based on disagreement with the amount. The only grounds to challenge an award in court are fraud, corruption, or a clear violation of law by the arbitrators — these are extremely rare.