Illinois Secretary of State has two types of driving records: a public record and a “court purpose driving record.”
The public record is one that your insurance company is allowed to obtain. Court supervision does not show on your public record however conviction do appear. If you are convicted for the DUI, (unlikely for a first offense) the DUI will appear and your car insurance company will see that you received a DUI and a conviction.
The “court purpose driving record” shows convictions and court supervisions. Unless you completely win the DUI, (statutory summary suspension and DUI charge) your court purpose record will reflect that you have received a DUI, statutory summary suspension, or court supervision for a DUI.
In other words, your car insurance company will not likely find out about your DUI provided: 1. You either win the case or receive court supervision and 2. you do not tell them about it yourself.