Illinois Headlight Laws: When You Must Use Them

Mandatory Headlight Conditions (625 ILCS 5/12-201)

Illinois requires headlights (not just DRLs) in these situations:

1. Sunset to sunrise. (Standard night driving.)
2. Visibility ≤500 feet: Fog, smoke, rain, snow, dust.
3. Windshield wipers in use: Continuous or intermittent—automatic with wipers.
4. All non-interstate highways: Any road not part of Interstate system (including US/IL routes, county roads, city streets).

Key Clarifications

• Interstates: Headlights not mandated by this statute solely for interstate driving (but required at night/low vis).
• DRLs ≠ Headlights: Daytime running lights don't satisfy requirement; must activate full headlight system (taillights on).
• Motorcycles: Headlight always required (modulating allowed).
• Penalty: Petty offense (~$75 + court costs); no points.

Best Practice

Use headlights anytime visibility is reduced or on any non-interstate road. Many drivers keep them on always—improves conspicuity, legal everywhere.