Illinois Oversize & Heavy Haul Permits: Key Regulations for Safe Transport

Permit Validity & Operating Hours

• Oversize permits: Valid for five days.
• Operating Time:
  • Loads up to 12′ wide, 13′-6″ high, and 200′ long can operate 24/7.
  • For loads up to 14′-6″ wide, 15′ high, and 200′ long, travel is allowed from 30 minutes before sunrise to 30 minutes after sunset, seven days a week.
  • Overweight-only loads with legal dimensions can travel continuously.

Restricted Travel Areas & Special Rules

• Cook County Expressways: Max 120,000 lbs, 12′ wide, and/or 13′-6″ high (additional restrictions apply).
• Width Restrictions (14′-6″ to 16′): Limited to 9:00 AM–3:00 PM, Monday–Friday in Cook, DuPage, Lake, Kane, Madison, McHenry, Monroe, St. Clair, and Will counties.
• Over 16′ wide: May face extra restrictions.
• No travel: From noon before major holidays or holiday weekends.

Illinois Toll Road Rules

• Max Width: 10′ (except 12′ on I-80 near Indiana & US-51 near Wisconsin).
• Weight Fees:
  • 80,001–104,000 lbs: ~$35
  • 104,001–120,000 lbs: ~$150
• Max Length: 100′ (longer requires special approval).
• Max Height: 14′-6″ (over 13′-6″ costs extra $15).

Legal Dimensions for Heavy Haul Trucks

• Length:
  • 53′ semi-trailers allowed on designated highways.
  • 65′ max on non-designated roads (kingpin to rear axle ≤ 45′-6″ or permit required).
• Overhang: 3′ front, 4′ rear (more rear overhang allowed if within legal length).
• Width: 8′-6″ (designated highways) / 8′ (non-designated).
• Height: 13′-6″.
• Weight Limits:
  • Gross: 80,000 lbs
  • Single Axle: 20,000 lbs
  • Tandem Axle: 34,000 lbs
  • Tridem Axle: 42,500 lbs

Routine Permit Limits

• Length: Up to 145′
• Width: Up to 14′-6″
• Height: Up to 15′ (must maintain 3″ clearance; over 15′-9″ banned on interstates).
• Weight:
  • Single Axle: 24,000 lbs
  • Tandem Axle: 48,000 lbs
  • Tridem Axle: 60,000 lbs (max 21,000 lbs per axle)

Superload Classification:

• 5+ axles >100,000 lbs or >44,000 lbs on a tandem.
• 6+ axles >120,000 lbs or >48,000 lbs on any group.

Lift/Pusher Axles: Max 2,000 lbs variance between axles in a group.

Over 16′ wide or 17′ high: Requires engineering review and utility coordination.

Exemptions

• No length permit needed for structural loads (beams, pipes, etc.) ≤80′ long (total ≤100′) transported weekdays, daytime.
• Farm equipment over width (but under 13′-6″ height/legal weight) can move without permits on weekends.

Escort Requirements for Oversize Loads

Proper oversize load escort services are critical for compliance:

• By Length:
  • >110′: 1 escort
  • >145′: 3 escorts
  • >200′: State Police
• By Width:
  • >14′-6″: 1 escort
  • >16′: 3 escorts
  • >18′: State Police
• By Height:
  • >14′-6″: 1 escort (with high pole)
  • >16′: Route survey + 1 escort
  • >18′: 2 escorts + State Police
• Combination Rule: Exceeding two dimensions? Two escorts minimum.

Signs, Flags & Lighting

• Flags: Required on all extremities of oversized loads.
• Signs: Mandatory for loads >10′ wide, >14′-6″ high, or >75′ long.
• Lights:
  • Amber rotating/flashing lights (visible 500+ feet daytime).
  • Second light required if load >80′ long or combo >100′ long.

Key Takeaways for Oversize Transport Logistics:

• Plan routes carefully—avoid restricted zones/times.
• Verify escort needs based on dimensions.
• Superloads require extra permitting and coordination.
• Utility checks are critical for tall/heavy loads.