About 40 percent of the drivers are NC Quick Pass customers.
Drivers carry transponders in their car which is automatically scanned as they pass through a toll.
NC Quick Pass directly pays toll money to the state.
The other 60 percent can expect to receive an invoice for the toll in the mail.
Cameras at the high speed toll booths captured pictures of drivers' license plate numbers and sent the bills to the addresses listed on the drivers' registration.
Officials said the cameras used to capture license plates do not take pictures of drivers. If the car is borrowed, the registered owner is responsible for the toll transactions (just like the registered owner would be responsible for parking tickets).
If the car is stolen (with the transponder in it), the NC Quick Pass customer must call 1-877-7MYPASS.
Those who don't pay their toll bills could face fines or the cancelation of their vehicle registration.
The Triangle Expressway's free run ended Jan. 3 and drivers have been charged 77 cents to pass through the 3.5 miles section one way.
The section of the Triangle Expressway that connects the Durham Freeway to Highway 540 opened in December.
The second phase of the project will run from Highway 55 all the way to U.S. 64. It is slated to open in August.