Illinois law requires drivers to give at least three feet of room when passing bicyclists.
Here in Illinois our statewide law requires operators of motor vehicles to provide bicyclists at least three feet of distance between the motor vehicle and the bicyclist. The term “The 3-Foot Rule” comes from sub-paragraph (d) of Section 11-703 of the Illinois Rules of the Road:
(625 ILCS 5/11‑703) (from Ch. 95 1/2, par. 11‑703) Sec. 11‑703. Overtaking a vehicle on the left. The following rules govern the overtaking and passing of vehicles proceeding in the same direction, subject to those limitations, exceptions, and special rules otherwise stated in this Chapter:
(d) The operator of a motor vehicle overtaking a bicycle or individual proceeding in the same direction on a highway shall leave a safe distance, but not less than 3 feet, when passing the bicycle or individual and shall maintain that distance until safely past the overtaken bicycle or individual.