Mysterious charges for thousands of Illinois Tollway drivers caused by extra digit in internal codes

An Illinois Tollway glitch that left thousands of drivers with unexpected warnings about unpaid tolls stemmed from an extra digit in codes within the system's computers, according to records obtained through a Freedom of Information Act request.

Meantime, the Illinois Tollway continued to refuse to answer questions about the glitch.

Andrew Cool was one of the dozens of people who reached out after CBS News Chicago following reporting on the mysterious old toll charges popping up on thousands of drivers' Illinois Tollway accounts.

He said he would have had no idea about $24 worth of unpaid tolls going back to 2024 if he hadn't checked his account because his transponder wasn't working.

"I had no idea. I was shocked when I saw it, especially from 2024," Cool said.

Dozens of drivers emailed CBS News Chicago detailing their frustration about never receiving notification or explanation from the Tollway about the mysterious warnings about unpaid tolls, even after trying to get help from customer service.

"Where is our money going? Obviously, their computers are not keeping track of these things," Cool said.

It turns out the problem appears to be an extra number. Internal emails received through a FOIA request show Illinois Tollway computers were getting four-digit codes starting in November, but their system is only designed to handle three digits.

That led a massive number of transactions to fail, and caused "significant processing backlogs," "late payment surcharges incorrectly applied," and "repeated failure of manual processing workarounds," according to Tollway emails.

What caused the extra digit error? It appears it was the Illinois Tollway's move away from plastic transponders, which started in 2024.

One tollway email connected the "4-digit error" to "when we switched over to sticker tags."

What does this mean for you tollway customers? An estimated 860,000 transactions were "incorrectly charged late/posting surcharges."

The emails suggest corrections would be made to the surcharges, but because customers never received notice of the initial issue, you wouldn't know if you were impacted nor if your account was fixed.

A tollway spokesperson initially told us 100,000 accounts were impacted, but documents obtained through a FOIA request show more than 200,000 "affected accounts."

A June 12 email from the tollway to its outside vendor that handles customer service said, "you may start to get some calls" about these errors.

Yet the tollway never directly notified its customers of this glitch.

In a statement on Wednesday, the Illinois Tollway still did not answer many of the questions CBS News Chicago has asked.

"The issue occurred as a result of multifaceted technological enhancements, one of which introduced new business rules.  The result was that certain video tolls did not post to less than 3% of our I-PASS customer accounts – approximately 170,000 out of about 5.8 million I-PASS customers.  Then, based on business rules governing invoicing, invoices did not issue until sufficient unpaid tolls accumulated.  For example, one of the business rules governing invoicing is that an invoice will not be issued until at least three tolls are missed.  Accordingly, if an unpaid toll occurred in January 2025 and the customer did not incur a third unpaid toll until November 2025, the customer would not receive an invoice until after November 2025.

After the above issue came to the Tollway's attention, the Tollway updated the logic and changed the video tolls back to the I-PASS rate.

The logic was updated at no additional cost to the Tollway, and no Tollway customer will pay anything more than the lowest I-PASS rate available."

Notably, the tollway's refusal to answer questions about the glitch comes as officials are seeking a $26.5 billion rate hike.