Originally Posted by mmo1184

One thing to note going off of what AppleBoy97 said is when I was in Chicago recently, I asked at the checkout booth how tolls worked since there don't appear to be anymore pay with cash booths. Apparently in Chicago from what I understood, the toll pass is $12 a day whether you use it or not unlike in other places where its just charged the days you use it and apparently its a physical pass with suction cups though checkout said they may change how they do tolls since Illinois changing to a sticker like other states. The $12 a day also includes unlimited tolls which sounds unbelievable but the website seems to corroborate that.

Since I was only planning on needing tolls a couple of days, I asked what else my options where and one of them was to to go to the Illinois Tollway website and enroll in pay by plate. You have up to two weeks after you drove through a toll to enroll or you can enroll in advance and with a rental car they highly recommend you include the dates of your rental so you are only charged for that time period. The website even is set up for cars with Fleet Plates like most Illinois rental cars. I was shocked at how efficient and well this pay by plate system worked. My first toll hit my credit card one week after I drove through.