What dispute deadlines should providers track in Illinois?

Accident Notice: Notice to insurer as soon as reasonably practicable; MedPay Claim Submission: Submission within standard policy billing deadlines (typically 1 to 3 years); Clean Claim Payment Window: 30 calendar days from receipt of clean claim (215 ILCS 5/368a). Verify the trigger date, current agency notices, and any extension before acting.

Which agencies administer these rules in Illinois?

The guide identifies Illinois Department of Insurance (IDOI). The correct agency depends on the plan and claim jurisdiction.

Auto Accident, PIP & Medical Billing State Guides

Illinois Auto Accident, PIP & Medical Billing Laws

Illinois operates an At-Fault automobile insurance framework under Chapter 215 and Chapter 735 of the Illinois Compiled Statutes (ILCS). Motor vehicle liability is governed by modified comparative fault with a 51% bar. Medical providers utilize optional first-party Medical Payments (MedPay) and enforce statutory healthcare provider liens under the Health Care Services Lien Act (770 ILCS 23), which caps total provider liens at 40% of tort proceeds.

Accountability & Review

Reviewed by Millennova Legal Operational Integrity Team, Senior Audit and Arbitration Analysts

Last Reviewed

2026-03-01

Plain-language overview

At-Fault / Traditional Tort (Health Care Services Lien Act 40% Cap & Common Fund Doctrine)

Illinois is an at-fault tort liability state that does not mandate Personal Injury Protection (PIP). Medical expenses arising from automobile collisions are funded through optional first-party Medical Payments (MedPay) coverage, commercial health insurance, or third-party auto liability insurance. When pursuing MedPay subrogation against a third-party recovery, insurers must contribute a one-third attorney fee under the Illinois Common Fund Doctrine (Baier v. State Farm). All healthcare professionals and facilities secure treatment balances through the Illinois Health Care Services Lien Act (770 ILCS 23), which establishes strict aggregate recovery caps.

PIP and MedPay coverage

Optional Med Pay Coverage

MedPay is optional in Illinois (commonly written in limits of $1,000 to $10,000+ per person), providing no-fault reimbursement for reasonable and necessary medical, surgical, dental, hospital, and ambulance expenses incurred within 1 to 3 years of the collision

Common Fund Doctrine

Under Illinois common law (Baier v. State Farm Ins. Co.), an insurer asserting a contractual subrogation lien against a third-party tort recovery must pay a pro-rata share (typically 33.3%) of the attorney fees and costs incurred by the claimant in generating the fund

Assignment Of Benefits

Healthcare providers routinely obtain patient assignments of MedPay benefits for direct claims submission to automobile insurers

Medical fee schedule and reimbursement rules

Name

Reasonable and Customary Fee Standard

Rules

Illinois does not establish a statutory fee schedule table for motor vehicle accident medical billing. Healthcare providers bill standard reasonable and customary fees prevailing in the local healthcare community for comparable care.

Cpt Basis

CPT/HCPCS itemized coding on standard CMS-1500 or UB-04 billing claims

Preauthorization and utilization review

Requirement

Preauthorization is not required by statute for emergency medical stabilization or initial acute management. Elective surgical interventions and prolonged physical therapy regimens are evaluated under insurer medical necessity guidelines.

Carrier Examinations

Under standard auto policy terms, insurers may request medical records or independent physician reviews to evaluate causal relationship to the motor vehicle crash.

Appeals and dispute resolution

Prompt Payment Statute

Under 215 ILCS 5/368a, an insurer must pay clean claims within 30 calendar days of receipt. Claims not paid within 30 days accrue statutory interest at the rate of 9% per year.

Health Care Services Lien Act

Under 770 ILCS 23/1 et seq., all healthcare professionals (physicians, chiropractors, physical therapists) and healthcare facilities (hospitals, surgery centers) have a statutory lien upon personal injury tort claims and verdicts. Total liens cannot exceed 40% of the gross verdict or settlement. No single category of providers (professionals vs. facilities) may receive more than 20% if total liens exceed 40%. Liens must be served via certified mail on the injured party and the liability insurer.

Dispute Forum

Illinois Circuit Court (county circuit court) for civil recovery actions and lien adjudication petitions under 770 ILCS 23/30.

Claim and dispute deadlines

Deadlines can depend on the trigger event and may be affected by agency relief notices. Confirm the live rule before filing.

Event	Timeframe
Accident Notice	Notice to insurer as soon as reasonably practicable
MedPay Claim Submission	Submission within standard policy billing deadlines (typically 1 to 3 years)
Clean Claim Payment Window	30 calendar days from receipt of clean claim (215 ILCS 5/368a)
Health Care Lien Service	Written notice served via certified mail prior to disbursement of settlement funds (770 ILCS 23/10)
Statute of Limitations	2 years from accident date for personal injury tort claims (735 ILCS 5/13-202); 10 years for written contracts

Documentation checklist

Illinois MedPay Claim Application Form
Executed Assignment of Benefits (AOB) and medical records authorization
Itemized CMS-1500 or UB-04 billing form with CPT/HCPCS codes and ICD-10 diagnostic coding
Contemporaneous medical records, emergency intake documentation, operative reports, and imaging findings
Written Notice of Health Care Services Lien served via certified mail with postal return receipts (770 ILCS 23/10)
Insurer Explanation of Benefits (EOB) or written explanation of claim determination

Responsible agencies

Illinois Department of Insurance (IDOI)Statewide Regulation of Auto Insurers, Rate Filings & Consumer Inquiries

Primary legal and regulatory sources

Illinois Compiled Statutes Chapter 770, Act 23 (Health Care Services Lien Act)Illinois General Assembly · 2024
Illinois Compiled Statutes Chapter 215, Section 5/368a (Timely Payment of Claims)Illinois General Assembly · 2024

This operational reference is educational, is not legal advice, and does not create an attorney-client relationship.

Common questions

What rules govern auto accident, pip & medical billing state guides in Illinois?: Illinois operates an At-Fault automobile insurance framework under Chapter 215 and Chapter 735 of the Illinois Compiled Statutes (ILCS). Motor vehicle liability is governed by modified comparative fault with a 51% bar. Medical providers utilize optional first-party Medical Payments (MedPay) and enforce statutory healthcare provider liens under the Health Care Services Lien Act (770 ILCS 23), which caps total provider liens at 40% of tort proceeds.
What dispute deadlines should providers track in Illinois?: Accident Notice: Notice to insurer as soon as reasonably practicable; MedPay Claim Submission: Submission within standard policy billing deadlines (typically 1 to 3 years); Clean Claim Payment Window: 30 calendar days from receipt of clean claim (215 ILCS 5/368a). Verify the trigger date, current agency notices, and any extension before acting.
Which agencies administer these rules in Illinois?: The guide identifies Illinois Department of Insurance (IDOI). The correct agency depends on the plan and claim jurisdiction.