The short answer
Most policies require you to notify the insurer “as soon as practicable” of an accident, claim, or lawsuit. In Illinois, that means within a reasonable time under the circumstances. Late notice can cost you coverage, but whether notice was late depends on several factors, not just the calendar.
Why it matters
Late notice is one of the most common and most avoidable reasons coverage is lost. Businesses often hold off because a claim seems small, seems uncovered, or seems likely to go away.
Where it fits in your case
As soon as you learn of an incident or claim that could involve insurance, often before any lawsuit is filed.
What to expect
How courts decide. Illinois courts consider the policy’s notice language, how sophisticated you are in business and insurance, when you became aware that the policy might apply, how diligently you acted afterward, and whether the insurer was harmed by the delay.
Harm to the insurer. Prejudice is one factor in deciding whether notice was reasonable. It is not a separate requirement the insurer always has to prove.
Claims-made policies are stricter. Professional liability and similar policies often require reporting within the policy period or a short window after. Those deadlines are frequently enforced strictly.
Your broker is not always the insurer. Telling your broker may not count as notice to the insurer.
Older policies. Policies from earlier years may still respond to claims arising from that period, even if the business has since changed or closed.
What to do now
Notify every potentially applicable insurer in writing, following each policy’s instructions.
Include older policies from the years when the events occurred.
Keep proof of when and how notice was sent.
If notice is late, explain the reasons in writing.
What we need from you
Your policies, the date you learned of the incident or claim, and any notices or communications already sent.
Common misconceptions
“Small claims don’t need to be reported.” Small claims can grow.
“Telling my broker is enough.” Not always.
“Late notice always defeats coverage.” Illinois weighs the circumstances.