IL SB3285

Establishes target service frequencies for intercity passenger rail routes originating from Chicago, categorized into hourly service (11 corridors including Chicago-Milwaukee, Chicago-St. Louis-Kansas City, and Chicago-Detroit-Toronto), every-2-hour service (3 corridors), and every-4-hour service (4 corridors) operating between 5 a.m. and 10 p.m.

Requires the Illinois Department of Transportation to incorporate these aspirational frequencies into the Illinois State Rail Plan and Long-Range Statewide Transportation Plan, and to include a recurring "Progress Toward High-Speed and Intercity Passenger Rail" section in plan updates.

Authorizes IDOT to nominate corridors for the Federal Railroad Administration's Corridor Identification and Development Program and enter into cooperative agreements with neighboring states for shared data and joint investment prioritization.

Mandates each Metropolitan Planning Organization in Illinois to recognize the target rail frequencies, identify relevant corridors in their planning areas, and explain how regional investments support achieving frequency goals during federally required plan updates.

Requires IDOT and MPOs to consider progress toward target passenger rail frequencies when developing project prioritization criteria for multimodal investments, and directs coordination with airport sponsors to address both landside access and airside capacity implications.