According to the Illinois Division of Insurance, after your policy has been in force more than 60 days, or if you have a renewal policy, your company may cancel you at any time if you fail to pay the premium by the due date.
The IL DOI does give a definition of a grace period as a time period after the due date that you may pay a premium without penalty. The policy remains in force during this time. But the DOI site goes on to say that not all insurance companies allow grace periods and there are no Illinois insurance laws requiring insurance providers to give you a grace period.
You will thus need to check with your insurance company to see if they have a grace period and if you can get your insurance reinstated. If you can, since your insurance was not in force at the time of the accident, than you still may not be covered for that incident.
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