Illinois oversize and overweight rules
The short answer
Last checked
Without a permit, a load in Illinois can be up to 8 ft 6 in wide, 13 ft 6 in high and 80,000 lb gross with 5 or more axles, with the conditions in the legal limits table. The first pilot car is required for loads over 14 ft 6 in wide or over 110 ft long, and a height pole car for loads over 14 ft 6 in high, with the conditions in the pilot car table. It treats a load as a superload when it is over 16 ft wide or 17 ft or more high; the conditions in the axle and fee tables name other superload triggers.
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Legal limits without a permit
| Limit | Up to | Roads | Rule |
|---|---|---|---|
| Width | 8 ft 6 inHolds on Class III and non-designated roads, and on Interstate and Class I or II roads, where safety devices are excluded from the width. | All roads | 625 ILCS 5/15-102(a), (e) |
| Height | 13 ft 6 in | All roads | 625 ILCS 5/15-103 |
| Length, single truck | 42 ftSemitrailers are exempt from this figure; buses and motor homes may run 45 feet. | All roads | 625 ILCS 5/15-107(a) |
| Length, semitrailer | 53 ftOn Class I highways, where combinations face no overall length limit; a semitrailer over 48 feet must keep kingpin to rear axle at 45 feet 6 inches or less. | Designated truck routes | 625 ILCS 5/15-107(d)(1) |
| Gross weight, 5 or more axles | 80,000 lbNeeds at least 5 axles; a vehicle with fewer axles falls under the bridge formula table. | All roads | 625 ILCS 5/15-111(a) |
Source: 625 ILCS 5/15-102, 625 ILCS 5/15-103, 625 ILCS 5/15-107, 625 ILCS 5/15-111
Axle weight limits
| Axle or group | Without a permit | With a permit | Roads |
|---|---|---|---|
| Any single axle | 20,000 lb | Not set | All roads |
| 2 axles in a group, spread over 3 ft 4 in to 8 ft | 34,000 lb | Not set | All roads |
| Gross weight, 5 or more axles | 80,000 lbNeeds at least 5 axles; a vehicle with fewer axles falls under the bridge formula table. | Not set | All roads |
| Gross weight, 6 or more axles | Not set | 120,000 lbIDOT’s practical maximum for a tractor semitrailer with 6 or more axles; a single unit with 4 or more axles is held to 76,000 pounds. Many bridges can’t carry even this, and heavier requests are considered as superloads. | All roads |
| Gross weight, 5 axles | Not set | 100,000 lbIDOT’s practical maximum for a five axle tractor and semitrailer; a five axle single unit is held to 76,000 pounds. Heavier requests are still considered, as superloads only if pavement and bridge stresses allow. | All roads |
| Gross weight, 4 axles | Not set | 76,000 lbOnly with axle spacing of 23 feet or more; one tandem may carry up to 34,000 pounds and the other up to 44,000. | All roads |
| Gross weight, 3 axles | Not set | 68,000 lbOnly with axle spacing of 18 feet or more, and at most 20,000 pounds on a single axle and 48,000 on the tandem. | All roads |
| Gross weight, 2 axles | Not set | 48,000 lbEach of the two axles is capped at 25,000 pounds. | All roads |
The bridge formula applies to axle groups on all roads (625 ILCS 5/15-111(a)). “With a permit” lists the state’s permit figures; read each row’s condition, since some are review thresholds rather than limits.
Pilot cars and escorts
Each row is one rule. A load can meet several; the permit lists the escorts for your move.
| Load | Roads | Front | Rear | Height pole | Police | |
|---|---|---|---|---|---|---|
| over 16 ft wideThe rule doesn’t give positions for the three escorts; ask the Permit Office. Moves over 16 feet wide also need a District investigation.Form OPER 993, Provision B, Escort Vehicles, third bullet | All roads | 2 in front, 1 behind | 2 | 1 | 0 | 0 |
| over 18 ft wideArrange the State Police escort with State Police headquarters at least 24 working hours ahead. The Permit Office can waive it in some cases, such as local police escorting inside a municipality.Form OPER 993, Provision B, Escort Vehicles, fourth bullet | All roads | police escort | 0 | 0 | 0 | 1 |
| over 14 ft 6 in up to 18 ft highThe escort carrying the height pole drives in front. A route survey by the carrier is needed from 16 feet high, and a District route survey from 17 feet.Form OPER 993, Provision B, Escort Vehicles, first bullet | All roads | 1 height pole car | 0 | 0 | 1 | 0 |
| over 18 ft highIDOT’s current permit form asks for three civilian escorts, while the Administrative Code says two. Neither gives their positions, so confirm them with the Permit Office.Form OPER 993, Provision B, Escort Vehicles, third bullet | All roads | 2 in front, 1 behind, 1 height pole car | 2 | 1 | 1 | 0 |
| over 18 ft highThe Permit Office can waive the State Police escort if a District investigation finds nothing overhead to obstruct the move.Form OPER 993, Provision B, Escort Vehicles, fourth bullet | All roads | police escort | 0 | 0 | 0 | 1 |
| over 145 ft longThe rule doesn’t give positions for the three escorts; ask the Permit Office.Form OPER 993, Provision B, Escort Vehicles, third bullet | All roads | 2 in front, 1 behind | 2 | 1 | 0 | 0 |
| over 200 ft longArrange the State Police escort with State Police headquarters at least 24 working hours ahead.Form OPER 993, Provision B, Escort Vehicles, fourth bullet | All roads | police escort | 0 | 0 | 0 | 1 |
| over 14 ft 6 in wide and over 14 ft 6 in highThe height pole rides on the lead escort.Form OPER 993, Provision B, Escort Vehicles, second bullet | All roads | 1 in front, 1 behind, 1 height pole car | 1 | 1 | 1 | 0 |
| over 14 ft 6 in high and over 110 ft longThe height pole rides on the lead escort.Form OPER 993, Provision B, Escort Vehicles, second bullet | All roads | 1 in front, 1 behind, 1 height pole car | 1 | 1 | 1 | 0 |
| over 14 ft 6 in wide and over 110 ft longForm OPER 993, Provision B, Escort Vehicles, second bullet | All roads | 1 in front, 1 behind | 1 | 1 | 0 | 0 |
| over 14 ft 6 in up to 16 ft wideA lone escort leads the load on a two-lane road, and the Permit Office can add a civilian escort for extra warning to the public.Form OPER 993, Provision B, Escort Vehicles, first bullet | Two-lane roads | 1 in front | 1 | 0 | 0 | 0 |
| over 110 ft up to 145 ft longA lone escort leads on a two-lane road, and every load travels with its own escort.Form OPER 993, Provision B, Escort Vehicles, first bullet | Two-lane roads | 1 in front | 1 | 0 | 0 | 0 |
| over 14 ft 6 in up to 16 ft wideA lone escort follows the load on a multilane divided road, and the Permit Office can add a civilian escort for extra warning to the public.Form OPER 993, Provision B, Escort Vehicles, first bullet | Two or more lanes in your direction | 1 behind | 0 | 1 | 0 | 0 |
| over 110 ft up to 145 ft longA lone escort follows on a multilane divided road, and every load travels with its own escort.Form OPER 993, Provision B, Escort Vehicles, first bullet | Two or more lanes in your direction | 1 behind | 0 | 1 | 0 | 0 |
- The lead pilot car is the one that carries the height pole.
Superloads
Illinois treats a load as a superload when it is any one of these:
- over 16 ft wide
- 17 ft or more high
Source: IDOT Form OPER 993 (Rev. 08/07/24), Provision B, Escort Vehicles, 92 Ill. Adm. Code 554.407, 554.408
When you can travel
Holidays
All permit moves (overweight-only categorical moves are exempt)
No movement on New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day, and none after noon the day before a holiday or holiday weekend. The rule gives no resume time; IDOT posts holiday-weekend details. 2026: Thanksgiving, noon Wed Nov 25; Christmas, noon Thu Dec 24; New Year 2027, noon Thu Dec 31.
Ill. Adm. Code 554.201(b)(3)-(5), 554.422Dates computed
Weekends
Overdimension permits
Saturday: half hour before sunrise to noon. Sunday: prohibited. Loads up to 12 ft wide, 13 ft 6 in high and 115 ft long (within practical maximum weights) may move 7 days, half hour before sunrise to half hour after sunset, except holidays. Overweight-only categorical permits run 24 hours, 7 days.
Night
Overdimension permits
On weekdays, half hour before sunrise to half hour after sunset; no night overdimension movement. Weekend hours are in the weekend entry. Superload hours are set on the permit, usually 9 a.m. to 3 p.m. Overweight loads at legal dimensions run 24 hours.
Cities and rush hour
Chicago (Central Business District Cermak to Division, Halsted to lake) and Cook County roads
City and county roads
Not a state curfew. The state rule sets the same travel times on State routes in Chicago and leaves City roads, including the Central Business District, to the City permit office. Cook County expressways bar loads over practical max weight, 12 ft wide or 13 ft 6 in high, except listed segments. City permit hours apply separately.
Every state on one page: holiday, weekend, night and city restrictions by state. For this year’s holiday, see Thanksgiving 2026 restrictions.
Single trip permit fees
Within each kind of fee the largest that fits your load applies, and the kinds add up.
| Fee | When it applies | Amount |
|---|---|---|
| Size fee625 ILCS 5/15-305, paragraph (a), Single Trip column, first 90 miles row, $12.00 | over 8 ft 6 in wide | $12 |
| Size fee625 ILCS 5/15-305, paragraph (a), Single Trip column, first 90 miles row, $12.00 | over 13 ft 6 in high | $12 |
| Size fee625 ILCS 5/15-305, paragraph (b), Single Trip column, first 90 miles row, $15.00 | over 10 ft wide | $15 |
| Size fee625 ILCS 5/15-305, paragraph (b), Single Trip column, first 90 miles row, $15.00 | over 70 ft long | $15 |
| Size fee625 ILCS 5/15-305, paragraph (c), Single Trip column, first 90 miles row, $25.00 | over 12 ft wide | $25 |
| Size fee625 ILCS 5/15-305, paragraph (c), Single Trip column, first 90 miles row, $25.00 | over 14 ft 6 in high | $25 |
| Size fee625 ILCS 5/15-305, paragraph (c), Single Trip column, first 90 miles row, $25.00 | over 85 ft long | $25 |
| Size fee625 ILCS 5/15-305, paragraph (d), Single Trip column, first 90 miles row, $30.00 | over 14 ft wide | $30 |
| Size fee625 ILCS 5/15-305, paragraph (d), Single Trip column, first 90 miles row, $30.00 | over 15 ft high | $30 |
| Size fee625 ILCS 5/15-305, paragraph (d), Single Trip column, first 90 miles row, $30.00 | over 100 ft long | $30 |
| Size fee625 ILCS 5/15-305, paragraph (e), Single Trip column, first 90 miles row, $50.00 | over 18 ft wide | $50 |
| Size fee625 ILCS 5/15-305, paragraph (e), Single Trip column, first 90 miles row, $50.00 | over 16 ft high | $50 |
| Size fee625 ILCS 5/15-305, paragraph (e), Single Trip column, first 90 miles row, $50.00 | over 120 ft long | $50 |
| Distance fee625 ILCS 5/15-305, Single Trip column | Every single trip permit | Not computed here, see the source |
| Weight fee625 ILCS 5/15-307(g); the in lieu schedules are in (b) to (f) | over 80,000 lb up to 120,000 lb gross | Not computed here, see the source |
| Weight fee625 ILCS 5/15-307(a), (b) to (g) | over 120,000 lb gross | $50 |
| Ton mile fee625 ILCS 5/15-307(g) | over 120,000 lb gross | Not computed here, see the source |
Where to apply
Illinois issues permits through Illinois Transportation Automated Permit system (ITAP). Apply at webapps.dot.illinois.gov.
Wind
- Manufactured and mobile homes over 12 ft wide must stop when gusts are over 25 mph (92 Ill. Adm. Code 554.422(a)(2)).
Source: 92 Ill. Adm. Code 554.422(a)(2)
What the rules don’t say
Where the sources are silent or say two things. Ask the state before you rely on these.
Legal limits
- Illinois legal semitrailer length differs by highway class. The 53 foot figure applies on the designated routes, so confirm the length limit for Class II and III highways before running a long trailer off them.
Axle weights
- Permit weight limits depend on vehicle type and axle position, with tandem maxima ranging from 34,000 to 60,000 pounds and spacing requirements of 18 or 23 feet for gross maxima. Confirm the figures for your exact configuration.
- Illinois’s permit rules (Part 554) don’t state a numeric weight for the heaviest moves; they are approved only if pavement and bridge stresses allow (§ 554.605). Off-road equipment over 30,000 pounds on a single axle may cross no structures (§ 554.609).
- Ask the permit office early about any move past 120,000 pounds, and about Cook County expressways, which bar loads over 120,000 pounds outside listed segments.
- Special vehicles such as mixers, refuse trucks, cranes on tracks, tow trucks and fire apparatus have their own axle limits. Local seasonal restrictions of up to 90 days a year and posted bridges also apply, so confirm both for your route.
- IDOT’s current permit form already cites a rewritten Part 554 that is not yet adopted; the Illinois Administrative Code is the version in force. Confirm the practical maximum weights before quoting a heavy move.
Pilot cars and superloads
- Illinois’s permit rules (Part 554) don’t state a numeric superload threshold; the permit office decides case by case. Ask whether your load will get a district investigation, which applies over 16 feet wide or at 17 feet high or more.
- For loads over 18 feet high, IDOT’s current permit form calls for three civilian escorts while the older Administrative Code text calls for two. Follow the permit as issued and confirm the count with the office.
- The rules don’t say where the third civilian escort travels or give a count for State Police escorts. Ask the office for the exact escort numbers and positions, and whether a State Police escort can be waived for your move.
- State Police escorts can also be required after a bridge analysis or investigation, and for overweight moves that must keep other traffic off a structure. Civilian escorts may be added for night or weekend emergency moves.
- Cook County expressways, toll roads and Chicago area controlled access highways carry their own limits. Check them separately for any route through that region.
- The Administrative Code also calls for three civilian escorts for towed special haul rigs over 150 feet long (92 Ill. Adm. Code 554.407(c)(3)), which IDOT’s permit form doesn’t list. Confirm the count with the office.
Permit fees
- Oversize fees step up with route length at 90, 180 and 270 miles, and the statute does not say whether each step is a total or an added amount. Confirm the fee for your actual mileage with IDOT before quoting.
- The statute is unclear on whether a load over several size limits pays one class fee or a separate fee for each dimension. Ask IDOT which applies to your load.
- From 80,001 to 120,000 pounds the overweight fee can follow a lower distance schedule for certain axle layouts and cranes. Over 120,000 pounds it is $50 plus 3.5 cents per ton mile over legal weight, so confirm the amount for your configuration.
- Engineering inspections run $40 an hour, and bridge or pavement analyses, IDOT escorts and State Police escorts are charged on top of permit fees. Ask for these amounts, which are not published as fixed prices.
- Mobile home moves, limited continuous operation permits, round trip permits and supplemental fees follow different fee rules. Confirm those fees directly if they apply to you.
Wind
- Illinois gives a wind number only for house trailers over 12 feet wide, which may not move when gusts exceed 25 mph. Other permit loads may not travel when State Police consider it unsafe, with no wind speed stated, so ask how they judge it.
- The rule does not say whether a manufactured home on a chassis counts as a house trailer. Confirm with the permit office before relying on the 25 mph line.
Where to apply
- Confirm with IDOT that ITAP is still the online system that takes applications before you rely on a bookmarked link.
Questions about Illinois
- When do I need an oversize permit in Illinois?
- Without a permit, a load in Illinois can be up to 8 ft 6 in wide, 13 ft 6 in high and 80,000 lb gross with 5 or more axles, with the conditions in the legal limits table. Loads past these figures generally need a permit from the state; see the legal limits table for the exceptions and for length, which depends on the vehicle.
- How much does an Illinois oversize permit cost?
- It depends on the load: the fee table shows which fees on the schedule we checked apply to which loads. Some charges are not computed here; the fee table names them. The estimator on this page adds up the fees for your load.
- When do you need a pilot car in Illinois?
- The first pilot car is required for loads over 14 ft 6 in wide or over 110 ft long, and a height pole car for loads over 14 ft 6 in high, with the conditions in the pilot car table. How many cars, and whether they lead or follow, depends on the road; the pilot car table lists each rule.
- What is a superload in Illinois?
- Illinois treats a load as a superload when it is over 16 ft wide or 17 ft or more high. The conditions in the axle and fee tables name other superload triggers. The superloads list on this page gives each threshold with its source.
- When can oversize loads travel in Illinois?
- At night: On weekdays, half hour before sunrise to half hour after sunset; no night overdimension movement. Weekend hours are in the weekend entry. Superload hours are set on the permit, usually 9 a.m. to 3 p.m. Overweight loads at legal dimensions run 24 hours. This applies to overdimension permits. On weekends: Saturday: half hour before sunrise to noon. Sunday: prohibited. Loads up to 12 ft wide, 13 ft 6 in high and 115 ft long (within practical maximum weights) may move 7 days, half hour before sunrise to half hour after sunset, except holidays. Overweight-only categorical permits run 24 hours, 7 days. This applies to overdimension permits.
- Can oversize loads move on holidays in Illinois?
- No movement on New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving Day and Christmas Day, and none after noon the day before a holiday or holiday weekend. The rule gives no resume time; IDOT posts holiday-weekend details. 2026: Thanksgiving, noon Wed Nov 25; Christmas, noon Thu Dec 24; New Year 2027, noon Thu Dec 31. This applies to all permit moves (overweight-only categorical moves are exempt).
Sources
- Illinois Vehicle Code, 625 ILCS 5/15-111: Wheel and axle loads and gross weights625 ILCS 5/15-111Illinois General Assembly, Legislative Reference Bureau. Read .
- 625 ILCS 5/15-103: Height of vehicles625 ILCS 5/15-103Illinois General Assembly. Read .
- 625 ILCS 5/15-107: Length of vehicles625 ILCS 5/15-107Illinois General Assembly. Read .
- 625 ILCS 5/15-102: Width of vehicles625 ILCS 5/15-102Illinois General Assembly. Read .
- 92 Ill. Adm. Code 554.604: Practical Maximum Weights92 Ill. Adm. Code 554.604Illinois Department of Transportation (rule); published by the Illinois General Assembly, Joint Committee on Administrative Rules. Read .
- 92 Ill. Adm. Code 554: Oversize and Overweight Permit Movements on State Highways92 Ill. Adm. Code 554Illinois Department of Transportation (rule); published by the Illinois General Assembly, Joint Committee on Administrative Rules. Read .
- IDOT Form OPER 993, Oversize and Overweight Permit Provisions, Provision B Oversize Provisions, Escort VehiclesIDOT Form OPER 993 (Rev. 08/07/24), Provision B, Escort VehiclesIllinois Department of Transportation, Permit Office. Read .
- 92 Ill. Adm. Code 554, Oversize and Overweight Permit Movements on State Highways (Illinois General Assembly, JCAR)92 Ill. Adm. Code 554.407, 554.408Illinois Department of Transportation (rule); published by the Illinois General Assembly, Joint Committee on Administrative Rules. Read .
- 92 Ill. Adm. Code 554.910, Fee for Engineering Inspections and Investigations92 Ill. Adm. Code 554.910Illinois Department of Transportation (regulation text published by the Joint Committee on Administrative Rules). Read .
- Illinois Vehicle Code, 625 ILCS 5/15-305, Fees for legal weight but overdimension vehicles, combinations, and loads625 ILCS 5/15-305Illinois General Assembly (statute enforced by the Illinois Department of Transportation). Read .
- Illinois Vehicle Code, 625 ILCS 5/15-307, Fees for overweight-gross loads625 ILCS 5/15-307(a), (b) to (g)Illinois General Assembly (statute enforced by the Illinois Department of Transportation). Read .
- Illinois Vehicle Code, 625 ILCS 5/15-311, Fees for Engineering Inspections or Field Investigations625 ILCS 5/15-311Illinois General Assembly (statute enforced by the Illinois Department of Transportation). Read .
- Illinois Vehicle Code, 625 ILCS 5/15-111, Wheel and axle loads and gross weights625 ILCS 5/15-111(a)Illinois General Assembly. Read .
- 92 Ill. Adm. Code 554.906, Basis for Fees (Oversize and Overweight Permit Movements on State Highways)92 Ill. Adm. Code 554.906Illinois Department of Transportation (rule); published by the Illinois General Assembly, Joint Committee on Administrative Rules. Read .
- 92 Ill. Adm. Code 554.422, When Moves May Be Made92 Ill. Adm. Code 554.422(a)(2)Illinois Department of Transportation (rule); published by the Illinois General Assembly Joint Committee on Administrative Rules. Read .
- Illinois Department of Transportation page naming the permit systemIllinois Department of Transportation, permit system pageIllinois Department of Transportation. Read .
Found something wrong or out of date? Report an error to hello@thirteensix.com.
This page is a dated summary in our own words, not legal advice. The permit the state issues governs your move, and states change their rules; check with Illinois before you travel.
Bordering states
- Crossing into Iowa? See Iowa rules
- Crossing into Indiana? See Indiana rules
- Kentucky, coming soon
- Crossing into Missouri? See Missouri rules
- Wisconsin, coming soon
More guides: all states and the rules library.
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