UM/UIM Arbitration in Illinois: Process and What to Expect

Most Illinois UM/UIM disputes resolve through contractual arbitration rather than court litigation. The arbitration clause appears in the auto policy itself and typically requires the parties—the injured insured and the carrier—to submit the dispute to one or three arbitrators who decide both liability and damages. Arbitration is faster than court but has its own procedural rules, evidence treatment, and strategic considerations. Awards are generally binding. Discovery in arbitration is typically more limited than in court litigation. Expert testimony is still central. Statute-of-limitations and notice rules in the policy contract must be met regardless of when arbitration is demanded.

Robert Parker leads Parker & Parker Attorneys at Law, a Peoria personal-injury practice founded by his father, Drew Parker, who is now retired. Robert Parker personally handles every case the firm accepts.

Why UM/UIM Cases Go to Arbitration

Auto policies in Illinois generally include an arbitration clause requiring UM/UIM disputes to be resolved through arbitration rather than court. The clause is enforceable under Illinois law. Arbitration is a contract process: the policy controls when it starts, how arbitrators are selected, what discovery is allowed, and whether any coverage issues must be decided by a court first.

Virtually all automobile policies issued today include arbitration provisions. The policy language governs the arbitration process. Where the policy is silent, arbitration may be unavailable, requiring a lawsuit or declaratory judgment.

Single-arbitrator vs. three-arbitrator panels

Many Illinois UM/UIM policies originally provided for three-arbitrator panels—one selected by each side, with the two party-selected arbitrators choosing a neutral third. Modern policies often use single-arbitrator panels through AAA or JAMS arbitration services. The structure is policy-specific.

High-low arbitrations

The parties sometimes negotiate a “high-low” agreement—the plaintiff is guaranteed at least the “low” number and the carrier pays at most the “high” number, regardless of the arbitrator’s award. The award fills the range. High-low agreements bound both sides’ exposure and are common in catastrophic cases where the parties want certainty on the floor and ceiling.

The Arbitration Procedure

Demand for arbitration

The arbitration process starts with a written demand under the policy’s arbitration clause. The demand identifies the claim, the policy and coverage at issue, the parties, and the relief sought. Most policies have contractual deadlines for demand; missing the deadline can waive the right to arbitrate.

Arbitrator selection

For single-arbitrator panels through AAA or JAMS, the administering organization typically circulates a list of qualified arbitrators; each side strikes names; the remaining candidate is appointed. For three-arbitrator panels, each side picks one and the two pick the neutral third.

Many UM/UIM arbitrations are governed by the Commercial Arbitration Rules of the American Arbitration Association. Rule 10 allows scheduling a mediation hearing first at no additional cost. Rule 10 also permits an administrative conference or preliminary hearing for scheduling and document production.

Discovery and pre-hearing process

Arbitration discovery is typically more limited than court discovery. Document exchange and a small number of depositions are common. Full expert disclosure cycles may or may not be required, depending on the arbitrator’s procedural orders. The arbitrator typically conducts a preliminary scheduling conference to set discovery, briefing, and hearing dates.

Limited discovery may restrict your ability to present the case. Depositions are allowed only if permitted by the rules. Document production must be agreed upon in the preliminary conference. Witness and exhibit identification is required in advance.

The hearing

UM/UIM arbitration hearings are typically held over one to three days. Plaintiff puts on liability evidence—police report, witnesses, accident reconstruction where appropriate—and damages evidence: medical records, treating-physician testimony, expert testimony on future care and economic loss, lay-witness testimony to functional impact. Defense puts on its own evidence, typically including an IME, defense neurology or orthopedics where injury is disputed, and economic-rebuttal testimony.

The award

The arbitrator or panel issues a written award typically within 30 to 60 days of the hearing. The award is final and binding under most policy arbitration clauses.

Arbitrators typically do not provide written explanations for awards. There are strict limits on vacating an arbitrator’s award, with no appellate review except in extremely limited circumstances, such as fraud. Limited grounds for vacating an arbitration award exist under 710 ILCS 5/12, including corruption, fraud, evident partiality, arbitrator misconduct that prejudiced a party, arbitrators exceeding their powers, refusal to hear material evidence, or no enforceable arbitration agreement in the circumstances described by the statute.

Arbitrators may act like mediators, requiring concessions from both sides. This “split-the-difference” tendency is a known risk in arbitration.

What You Waive in Arbitration

When you agree to arbitration, you waive your right to a jury trial. This is a constitutional waiver that requires careful consideration. The arbitration process is different from court litigation in several important ways:

• No written opinions explaining the arbitrator’s reasoning
• Limited appeal rights
• Arbitrators may split the difference rather than decide the case on the merits
• Discovery is more limited than in court

Preparing the Arbitration File

UM/UIM arbitration is still an evidence presentation. The record is usually leaner than a jury trial, but the proof has to be organized before the hearing date.

Liability proof

The injured insured still has to prove the uninsured or underinsured driver was legally responsible. In a car or truck crash, that usually means the police report, witness statements, photographs, vehicle-damage evidence, scene diagrams, crash reconstruction where needed, and any traffic citation or criminal disposition. In a hit-and-run case, the liability proof also has to establish the unidentified-driver predicate.

Medical proof

Medical proof includes emergency records, diagnostic imaging, treating-physician notes, therapy records, surgical records, impairment opinions where appropriate, future-care opinions, and billing records. The arbitration format can make records easier to present than a jury trial, but serious disputes still require live or deposition testimony from treating physicians and retained experts.

Economic proof

Lost earnings, future earning loss, and future medical care need documentation. The file may include wage records, tax returns, employer statements, vocational opinions, economist calculations, and life-care planning. Future economic damages still need present-cash-value treatment where the law requires it.

Coverage proof

The coverage file is separate from the damages file. It includes the declarations page, full policy, endorsements, UM/UIM selection or rejection forms, proof of notice, settlement-consent correspondence, exhaustion proof, and any stacking analysis. A strong injury presentation cannot fix a coverage defect, so the policy record is built early.

After the Award

After an award, the next step depends on the policy language and whether the award is within the available UM/UIM limits. In a straightforward binding arbitration, the insurer pays the covered amount, subject to policy limits, reductions, medical liens, attorney fees, litigation costs, and any required settlement accounting. In a UIM case, the final number must account for what was actually recovered from the at-fault driver’s liability coverage.

If a party seeks to challenge the award, the challenge is narrow and time-sensitive. Courts do not retry the merits of the injury case just because one side dislikes the result. The argument has to fit within the limited statutory vacatur or modification grounds. That is why the hearing record matters: exhibits, objections, expert disclosures, and procedural orders should be clear enough that the award can be defended if challenged.

Liens and distribution

UM/UIM recovery may be subject to health-insurance reimbursement claims, Medicare or Medicaid issues, medical-provider liens, workers’ compensation liens, or litigation-cost reimbursement. The arbitration award is not the end of the file; the final client distribution depends on lien resolution and settlement accounting.

Strategic Considerations

Choice of forum

Even where arbitration is contractually required, declaratory-judgment actions over coverage interpretation may proceed in court. Strategic timing of declaratory-judgment filings versus arbitration demands shapes case posture.

Evidence and expert testimony

Arbitration evidence rules are more flexible than the Illinois Rules of Evidence in court trials. Hearsay is often admitted with the arbitrator weighing it accordingly; expert testimony does not require the same disclosure cycles. The flexibility cuts both ways—plaintiffs can get evidence in without strict-rule barriers, but so can defense.

Settlement during arbitration

Most UM/UIM arbitrations settle before the hearing or during the hearing. The arbitration process itself often surfaces the value range, and a mediated resolution before the award is common.

Vacatur risk

Arbitration awards are difficult to vacate. The statutory grounds are narrow: corruption or fraud, evident partiality, prejudicial misconduct, arbitrators exceeding their powers, refusal to postpone for sufficient cause, refusal to hear material evidence, or no enforceable arbitration agreement where the statutory conditions are met. Practical effect: the arbitrator’s award is generally final. Cases proceed with that understanding.

Damages in UM/UIM Arbitration

Damages presentation in UM/UIM arbitration follows the same framework as a court trial under the Illinois Pattern Jury Instructions: medical expense, pain and suffering, disability, loss of a normal life, disfigurement, lost earnings, and future losses where supported by the evidence. Future economic damages are reduced to present cash value under the Illinois Pattern Jury Instructions, including IPI 34.02 where applicable. The arbitrator makes findings on each category supported by the evidence.

UIM reductions apply—under 215 ILCS 5/143a-2(4), UIM limits are reduced by amounts actually recovered from the applicable liability coverage. UM awards on a hit-and-run or uninsured-driver case typically do not have an underlying-liability reduction because there is no identified liability insurer paying the claim.

Local Context

UM/UIM arbitrations involving central-Illinois plaintiffs are typically administered through AAA or JAMS Chicago offices, with hearings held in Peoria or another locality convenient to the parties. Parker & Parker’s UM/UIM arbitration practice covers cases across the firm’s central-Illinois trade area.

When the plaintiff lives in Peoria, Tazewell, Woodford, McLean, or Knox County, local medical and witness proof often matters even if the arbitration administrator is based in Chicago. Treating providers at OSF Saint Francis Medical Center, Carle Health Methodist Hospital, Carle Health Proctor Hospital, and Carle BroMenn may supply the injury record. Local witnesses, employers, and family members supply the functional-impact proof that gives the medical record context.

Frequently Asked Questions

What is UM/UIM arbitration?

A contractual process under the auto policy that requires uninsured and underinsured motorist disputes to be resolved through arbitration rather than court litigation. The arbitrator decides both liability—was the at-fault driver negligent—and damages—what the injury is worth—and issues a binding written award.

Do I have to go to arbitration?

If your auto policy contains an arbitration clause—and most modern Illinois auto policies do—UM/UIM disputes go to arbitration rather than court. Some coverage-interpretation issues may proceed as declaratory-judgment actions in court even where the underlying liability and damages dispute goes to arbitration.

How long does UM/UIM arbitration take?

The full process—from demand to award—typically runs 9 to 18 months. Faster on simpler cases, slower on catastrophic-injury cases requiring extensive expert testimony.

Is the arbitration award final?

Yes, in most cases. Grounds for vacating an arbitration award are narrow under 710 ILCS 5/12. The award is functionally final.

What is a high-low agreement?

A side-agreement between plaintiff and carrier that the plaintiff is guaranteed at least the “low” amount and the carrier pays at most the “high” amount, regardless of the arbitrator’s actual award. High-low agreements bound both parties’ exposure and are common in catastrophic cases.

What if the carrier denies coverage entirely?

Coverage disputes may proceed as declaratory-judgment actions in court rather than as part of the liability and damages arbitration. Parker & Parker sometimes structures cases with parallel court and arbitration proceedings depending on the dispute.

How does my regular auto insurance pay if the at-fault driver had insurance?

When the at-fault driver had liability coverage but it was inadequate to compensate the full injury, your UIM coverage may apply after the liability recovery is accounted for. Illinois law reduces UIM limits by amounts actually recovered from the applicable liability coverage. Stacking analysis can affect the available UIM ceiling across household policies—see the Stacking UM/UIM Coverage in Illinois page.

Related Resources

• UM/UIM Hub (Parent)
• Stacking UM/UIM Coverage in Illinois
• Hit-and-Run UM Coverage in Illinois
• Car Accident Hub
• Truck Accident Hub
• Case Results

Speak With a Peoria UM/UIM Attorney

Rob Parker personally handles every UM/UIM case the firm accepts. Initial consultation free. Contingency: no fee unless we recover. 300 NE Perry Avenue, Peoria, IL 61603. (309) 673-0069.