Illinois Oversize & Overweight Permit Requirements & Rules (2026)

In Illinois, any load that exceeds the legal size or weight limits requires an oversize/overweight permit before it moves. Below are the legal limits and the requirements that apply at each threshold.

1When you need a permit

A load is oversize or overweight once it passes any of these:

Dimension	Illinois legal limit	Permit if over
Width	8 ft 6 in	Wider
Height	13 ft 6 in	Taller
Length (combination)	65 ft	Longer
Gross weight	80,000 lbs	Heavier
Single axle	20,000 lbs	Heavier
Tandem axle	34,000 lbs	Heavier

Rear overhang is limited to 4 ft and front overhang to 3 ft before it counts toward length, and any overhang must be flagged.

2Escort & pilot car requirements

When the load reaches…	Illinois requires
14.5 ft wide	1 escort (pilot car)
14.5 ft wide	2 escorts
14.5 ft high	Escort with a height pole / pole car
110 ft long	1 escort · 145 ft → 2 escorts
15 ft high or 14.5 ft wide	Route survey required
18 ft wide	Police escort

3When you can travel

Daylight only — 30 min before sunrise to 30 min after sunset.
Weekend travel allowed within dimensional limits.
Overweight-only (legal dimensions) may travel 24/7; OD loads are daylight-only.
Holiday blackouts: New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, Christmas.

4Superloads in Illinois

A load is a superload once it exceeds any of these:

Superload trigger	Threshold
Width	15.5 ft
Height	15 ft
Length	145 ft
Gross weight	150,000 lbs

Superloads require a route survey and roughly 3 days of lead time for approval.

5Permit timing

Standard single-trip: ~1 business day to issue.
Superload: ~3 days (route survey + review).
Validity: a single-trip permit is good for ~5 days.

Get the full cost of your load

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Note: these requirements are for planning and are verified as of May 2026. Rules change — always confirm with the state permitting authority before dispatch.

?Illinois permit FAQ

When do I need an oversize permit in Illinois?

Once a load exceeds any legal limit: 8 ft 6 in wide, 13 ft 6 in high, 65 ft long (combination), or 80,000 lbs gross.

When do I need a pilot car in Illinois?

Illinois requires one escort at 14.5 ft wide (two at 14.5 ft), a height pole at 14.5 ft high, and a police escort at 18 ft wide.

Can you drive an oversize load at night in Illinois?

No — oversize loads move daylight-only, 30 min before sunrise to 30 min after sunset. Weekend travel is allowed within limits.

What counts as a superload in Illinois?

Over 15.5 ft wide, 15 ft high, 145 ft long, or 150,000 lbs gross. It requires a route survey and about 3 days of lead time.

How much does a Illinois oversize permit cost?

The state permit fee depends on the load's size and weight. The full cost of a move also includes escorts, police, route surveys, engineering, and the truck rate, which vary by route. FreightDeck estimates all of it for your exact load — price your Illinois load with FreightDeck →.