Illinois Statute of Limitations for Diagnostic Medical Malpractice

HM&M
Jun 3
2 min read

If a doctor failed to diagnose your condition correctly or in a timely manner—and that mistake caused you harm—you may have a claim for diagnostic medical malpractice. However, Illinois law places strict time limits on how long you have to file a lawsuit. These deadlines are known as statutes of limitations.

Here’s what you need to know about the statute of limitations for diagnostic malpractice in Illinois:

Standard Filing Deadline: 2 Years from Discovery

Under 735 ILCS 5/13-212, patients have two years to file a lawsuit from the date they knew or reasonably should have known that:

They were injured, and
The injury may have been caused by a healthcare provider’s error

In the case of diagnostic malpractice, this typically means two years from the date:

You received the incorrect diagnosis
You learned the correct diagnosis and connected it to a delay or mistake
A second doctor or medical provider identified the error

Maximum Time Limit: 4-Year Statute of Repose

Even if you didn’t immediately discover the malpractice, Illinois law bars all diagnostic malpractice claims after four years from the date of the alleged misdiagnosis or failure to diagnose—regardless of when you discovered the error.

This deadline is known as the statute of repose and applies even in cases involving hidden conditions or slow-developing illnesses.

Exception for Minors

If the patient was a minor (under 18) at the time of the malpractice:

They have up to eight years from the date of the alleged act or omission to file
However, the claim must still be filed before the child’s 22nd birthday, even if the eight-year period has not expired

Exception for Legal Disabilities

If the patient was under a legal disability (such as a mental health condition) at the time the malpractice occurred, the statute of limitations does not begin to run until the disability is removed.

What Triggers the Clock?

The statute of limitations clock starts ticking when:

You discover that your symptoms were misdiagnosed or ignored, or
A reasonable person in your position should have known something was wrong based on worsening symptoms or a later-corrected diagnosis

This is often referred to as the “discovery rule.” However, courts interpret this rule strictly, so timing is critical.

Why Time Matters

If you file a diagnostic malpractice claim even one day late, your case may be dismissed—no matter how strong your evidence is. That’s why it’s essential to speak with an attorney as soon as you suspect a medical error.

Speak to a Diagnostic Malpractice Attorney in Illinois

At Hurley McKenna & Mertz, P.C., we help patients and families throughout Illinois navigate complex medical malpractice claims, including those involving missed or delayed diagnoses. We can review your records, determine if your claim falls within the legal deadlines, and take swift action to protect your rights.

Serving patients in Chicago, Cook County, and across Illinois.