Illinois Oversize & Overweight Permit Rules
What a load can be in Illinois without a permit, where the permit and escort tiers start on 2-lane roads and multi-lane roads, when it can move, and who to call. Every figure is the JaloPermit Atlas entry for Illinois, shown as the app shows it.
Rules as of Jul 31, 2026 · Links checked Jul 13, 2026
Read this before you trust a number. Rules change. The issued permit, posted signs and the state permit office always win over this page. JaloPermit is a reading aid, not a permit-filing service. Guests get 3 free decodes a day with no account and no card, logged-in users get 10 a day, and extra decodes are $3.50 each with no subscription.
What moves in Illinois without a permit
Legal limits are the dimensions and gross weight a vehicle may run at without an oversize or overweight permit. Illinois publishes its length limit as semitrailer, so compare it against that measurement on your permit, not the overall rig.
Where the permit and escort tiers start
| Dimension | Legal without permit | Permit tier starts | First escort on 2-lane roads | First escort on multi-lane roads |
|---|---|---|---|---|
| Width | 8'6" | 8'7" | 14'7" · Front escort | 14'7" · Rear escort |
| Height | 13'6" | 13'7" | 14'7" · Front + High pole | 14'7" · Front + High pole |
| Length | 53'0"semitrailer | 53'1" | 110'1" · Front escort | 110'1" · Rear escort |
| Weight | 80,000 lbs | 150,001 lbs | No escort tier (permit only) | No escort tier (permit only) |
"Permit tier starts" is the lowest size in the Atlas ladder that needs a permit. "First escort" is the lowest size that adds a private or police escort on that road class; the full ladder with each tier's rule and source is below.
Illinois escort ladder, tier by tier
Open a tier to read the rule behind it, quoted with its source. Amber tiers add a police escort or a superload review; grey tiers are permit-only with conditions.
On 2-lane roads
Escorts begin at 14'7" wide
Width
Permit required8'7" – 14'6"
Permit required over 8'6" legal width. No escort by width alone at or under 14'6": 92 IAC 554.407(a)(1) triggers only for moves that EXCEED 14'6" wide. Conditional escort: oversize loads at or under 12'0"W x 13'6"H x 200'L may move 24/7 but need one additional civilian escort during hours of darkness (OPER 993); over 12'0" wide is daylight-only. A civilian escort is also required for emergency moves during darkness or weekends (554.407(a)(4)).
Front escort14'7" – 16'
One civilian escort, 92 IAC 554.407(a)(1) (exceeds 14'6" wide). Position per 554.408(d): on a TWO-LANE highway the escort travels AHEAD of the load, about 300 ft in front in rural areas (554.408(e)) — roadClass non_interstate approximates Illinois' two-lane category; on a non-interstate multilane divided highway the escort trails instead. Combination rule: if the move ALSO exceeds 14'6" high or 110' long, two civilian escorts, one front and one behind (554.407(b)). Collar/metro county 9am-3pm Mon-Fri window applies >14'6"-16' wide (OPER 993 C.9(a)). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear16'1" – 18'
Three civilian escorts, 92 IAC 554.407(c)(1) (exceeds 16' wide); same in OPER 993. One leads and one trails per 554.408(d); the third escort's placement is set by the permit. Over 16' wide: statewide movement restricted to 9am-3pm Mon-Fri (OPER 993). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear + Police18'1"+
Three civilian escorts (554.407(c)(1)) PLUS a mandatory Illinois State Police escort (554.407(d)(1)(A): moves greater than 18' wide). That is at least 4 vehicles: 3 civilian escorts plus at least 1 State Police escort; ISP sets the actual police-vehicle count ('One or more ISP escorts shall be required', OPER 993 C.11). Arrange with ISP HQ 217/782-6527 at least 24 hours before the move (554.407(d)(2)). Local police may substitute when the move stays within a city or county (554.407(e)); the Permit Office may waive ISP in limited 554.407(d)(2) instances. Open-ended band: the rule text sets no upper width bound. A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Height
Permit required13'7" – 14'6"
Permit required over 13'6" legal height. No escort by height alone at or under 14'6": 92 IAC 554.407(a)(3) triggers only for moves that EXCEED 14'6" high. Daylight-only: over 13'6" high is not eligible for the OPER 993 24/7 night window. A civilian escort is required for emergency moves during darkness or weekends (554.407(a)(4)).
Front + High pole14'7" – 16'
One civilian escort with height pole, leading the load: 92 IAC 554.407(a)(3) (exceeds 14'6" high); 554.408(k) requires a vertical-clearance pole on escorts leading loads in excess of 14'6" high; 554.408(e) requires the height-pole escort to travel in front on all highway types. Combination rule: if also over 14'6" wide or 110' long, two civilian escorts front and rear (554.407(b)). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + High pole16'1" – 18'
One civilian escort with height pole, leading (92 IAC 554.407(a)(3)): the one-escort rule covers ALL single-dimension moves exceeding 14'6" high up to and including 18'; two escorts begin only when exceeding 18' high (554.407(b)(1)) or when a second dimension trigger is also exceeded (554.407(b)(2)-(4)). OPER 993 agrees. Corrects the prior unsourced 2-escort value (verifier-confirmed July 2026 finding). Over 17' high: statewide 9am-3pm Mon-Fri movement window (OPER 993). Tier kept split at 16' to preserve published tier geometry and the differing travel windows. A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear + High pole + Police18'1"+
Three civilian escorts (OPER 993 Rev. 08/07/24: three required for moves that 'exceed 18ft 0in high') PLUS a mandatory Illinois State Police escort (554.407(d)(1)(C): moves over 18' high) : at least 4 vehicles, 3 civilian escorts plus at least 1 State Police escort. Source conflict documented: 92 IAC 554.407(b)(1) (2012) says TWO civilian escorts over 18' high; the newer OPER 993 says THREE — the more restrictive reading is encoded. ISP may be waived only if a field investigation reveals no overhead obstructions (554.407(d)(2)(C)). The height-pole escort leads (554.408(e),(k)). Arrange ISP 24 hours ahead, 217/782-6527. A police escort is required over 18 ft high, in addition to the private escorts. Source: 92 Ill. Adm. Code 554.407 When Escort Vehicles Are Required (also IDOT Form OPER 993 Provision B). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Length
Permit required53'1" – 110'
Permit required beyond legal length. No escort by length alone at or under 110': 92 IAC 554.407(a)(2) triggers only for moves that EXCEED 110' long. Conditional escort: loads at or under 200' long (and at or under 12'0" wide, 13'6" high) may move 24/7 with one additional civilian escort during darkness (OPER 993). Emergency darkness/weekend moves require a civilian escort (554.407(a)(4)).
Front escort110'1" – 145'
One civilian escort, 92 IAC 554.407(a)(2) (exceeds 110' long). Position per 554.408(d): leads the load about 300 ft ahead on two-lane highways (554.408(e)) — non_interstate approximates Illinois' two-lane category; on a non-interstate multilane divided highway the escort trails instead. Combination rule: if also over 14'6" wide or 14'6" high, two civilian escorts front and rear (554.407(b); OPER 993). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear145'1" – 200'
Three civilian escorts, 92 IAC 554.407(c)(2) (exceeds 145' long); 554.407(c)(3) independently requires three for all towed special haul rigs more than 150' long. One leads, one trails (554.408(d)); third placement set by permit. A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear + Police200'1"+
Three civilian escorts (554.407(c)(2)) PLUS a mandatory Illinois State Police escort (554.407(d)(1)(B): moves of greater than 200' in length) : at least 4 vehicles, 3 civilian escorts plus at least 1 State Police escort ('One or more ISP escorts', OPER 993 C.11). No Saturday or Sunday movement over 200' long (OPER 993). Arrange ISP 24 hours ahead, 217/782-6527; local police in lieu within a municipality (554.407(e)). Open-ended: rule text sets no upper length bound. A police escort is required over 200 ft long, in addition to the private escorts. Source: 92 Ill. Adm. Code 554.407 When Escort Vehicles Are Required (also IDOT Form OPER 993 Provision B). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Weight
Permit required150,001 lbs+
No escort is set by weight alone in Illinois. An Illinois State Police escort is required only when the permit's bridge restrictions keep all other traffic off a structure while the load crosses, or when IDOT's Bridge Office analysis calls for one; the permit then states it. Source: 92 Ill. Adm. Code 554.407 (amended eff. 8/1/2012); IDOT Form OPER 993 (2024).
On multi-lane roads
Escorts begin at 14'7" wide
Width
Permit required8'7" – 14'6"
Permit required over 8'6" legal width. No escort by width alone at or under 14'6": 92 IAC 554.407(a)(1) triggers only for moves that EXCEED 14'6" wide. Conditional escort: oversize loads at or under 12'0"W x 13'6"H x 200'L may move 24/7 but need one additional civilian escort during hours of darkness (OPER 993); over 12'0" wide is daylight-only. A civilian escort is also required for emergency moves during darkness or weekends (554.407(a)(4)).
Rear escort14'7" – 16'
One civilian escort, 92 IAC 554.407(a)(1) (exceeds 14'6" wide). Position per 554.408(d): on a multilane divided highway the escort TRAILS the load — roadClass interstate approximates Illinois' multilane-divided category. Combination rule: if the move ALSO exceeds 14'6" high or 110' long, two civilian escorts are required, one in front and one behind (554.407(b); OPER 993). In Cook, DuPage, Lake, Kane, Madison, McHenry, Monroe, St. Clair and Will counties, >14'6"-16' wide moves run 9am-3pm Mon-Fri only (OPER 993 Provision C.9(a)). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear16'1" – 18'
Three civilian escorts, 92 IAC 554.407(c)(1) (exceeds 16' wide); same in OPER 993. One leads and one trails per 554.408(d); the third escort's placement is set by the permit. Over 16' wide: statewide movement restricted to 9am-3pm Mon-Fri (OPER 993). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear + Police18'1"+
Three civilian escorts (554.407(c)(1)) PLUS a mandatory Illinois State Police escort (554.407(d)(1)(A): moves greater than 18' wide). That is at least 4 vehicles: 3 civilian escorts plus at least 1 State Police escort; ISP sets the actual police-vehicle count ('One or more ISP escorts shall be required', OPER 993 Provision C.11). Arrange with ISP HQ 217/782-6527 at least 24 hours before the move (554.407(d)(2)). Local police may substitute when the move stays within a city or county (554.407(e)); the Permit Office may waive ISP in limited 554.407(d)(2) instances. Open-ended band: the rule text sets no upper width bound; moves this size are individually engineered. A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Height
Permit required13'7" – 14'6"
Permit required over 13'6" legal height. No escort by height alone at or under 14'6": 92 IAC 554.407(a)(3) triggers only for moves that EXCEED 14'6" high. Daylight-only: over 13'6" high is not eligible for the OPER 993 24/7 night window. A civilian escort is required for emergency moves during darkness or weekends (554.407(a)(4)).
Front + High pole14'7" – 16'
One civilian escort with height pole, leading the load: 92 IAC 554.407(a)(3) (exceeds 14'6" high); 554.408(k) requires a vertical-clearance pole on escorts leading loads in excess of 14'6" high; 554.408(e) requires the height-pole escort to travel in front. Combination rule: if also over 14'6" wide or 110' long, two civilian escorts front and rear (554.407(b)). RETAINED UNVERIFIED from prior data: interstate practical max height 15'9" and route survey over 15'6" — no Tier-1 text found this session; confirm with IDOT Permit Office. A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + High pole16'1" – 18'
One civilian escort with height pole, leading (92 IAC 554.407(a)(3)): the one-escort rule covers ALL single-dimension moves exceeding 14'6" high up to and including 18'; two escorts begin only when exceeding 18' high (554.407(b)(1)) or when a second dimension trigger is also exceeded (554.407(b)(2)-(4)). OPER 993 agrees. Corrects the prior unsourced 2-escort value (verifier-confirmed July 2026 finding). Over 17' high: statewide 9am-3pm Mon-Fri movement window (OPER 993). Tier kept split at 16' to preserve published tier geometry and the differing travel windows. A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear + High pole + Police18'1"+
Three civilian escorts (OPER 993 Rev. 08/07/24: three required for moves that 'exceed 18ft 0in high') PLUS a mandatory Illinois State Police escort (554.407(d)(1)(C): moves over 18' high) : at least 4 vehicles, 3 civilian escorts plus at least 1 State Police escort. Source conflict documented: 92 IAC 554.407(b)(1) (2012) says TWO civilian escorts over 18' high; the newer OPER 993 says THREE — the more restrictive reading is encoded. ISP may be waived only if a field investigation reveals no overhead obstructions (554.407(d)(2)(C)). The height-pole escort leads (554.408(e),(k)). Arrange ISP 24 hours ahead, 217/782-6527. A police escort is required over 18 ft high, in addition to the private escorts. Source: 92 Ill. Adm. Code 554.407 When Escort Vehicles Are Required (also IDOT Form OPER 993 Provision B). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Length
Permit required53'1" – 110'
Permit required beyond legal length. No escort by length alone at or under 110': 92 IAC 554.407(a)(2) triggers only for moves that EXCEED 110' long. Conditional escort: loads at or under 200' long (and at or under 12'0" wide, 13'6" high) may move 24/7 with one additional civilian escort during darkness (OPER 993). Emergency darkness/weekend moves require a civilian escort (554.407(a)(4)).
Rear escort110'1" – 145'
One civilian escort, 92 IAC 554.407(a)(2) (exceeds 110' long). Trails the load on multilane divided highways per 554.408(d) — interstate approximates multilane-divided. Combination rule: if also over 14'6" wide or 14'6" high, two civilian escorts front and rear (554.407(b); OPER 993). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear145'1" – 200'
Three civilian escorts, 92 IAC 554.407(c)(2) (exceeds 145' long); 554.407(c)(3) independently requires three for all towed special haul rigs more than 150' long. One leads, one trails (554.408(d)); third placement set by permit. A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Front + Rear + Police200'1"+
Three civilian escorts (554.407(c)(2)) PLUS a mandatory Illinois State Police escort (554.407(d)(1)(B): moves of greater than 200' in length) : at least 4 vehicles, 3 civilian escorts plus at least 1 State Police escort ('One or more ISP escorts', OPER 993 C.11). No Saturday or Sunday movement over 200' long (OPER 993). Arrange ISP 24 hours ahead, 217/782-6527; local police in lieu within a municipality (554.407(e)). Open-ended: rule text sets no upper length bound. A police escort is required over 200 ft long, in addition to the private escorts. Source: 92 Ill. Adm. Code 554.407 When Escort Vehicles Are Required (also IDOT Form OPER 993 Provision B). A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
Weight
Permit required150,001 lbs+
No escort is set by weight alone in Illinois. An Illinois State Police escort is required only when the permit's bridge restrictions keep all other traffic off a structure while the load crosses, or when IDOT's Bridge Office analysis calls for one; the permit then states it. Source: 92 Ill. Adm. Code 554.407 (amended eff. 8/1/2012); IDOT Form OPER 993 (2024).
When more than one size needs an escort
A move over two of 14'6" wide, 14'6" high and 110 ft long needs two civilian escorts, one ahead and one trailing (92 Ill. Adm. Code 554.407(b), 554.408).
When a permitted load can move
- Standard hours
Depends on size. Overweight-only permits at legal dimensions run 24/7. Oversize at or under 12'0" wide, 13'6" high, 200' long also runs 24/7 but needs one extra civilian escort during darkness. Up to 14'6" wide, 15'0" high, 200' long: 1/2 hr before sunrise to 1/2 hr after sunset.
- Night travel
Permitted for some loads. Overweight-only at legal dimensions: 24/7. Oversize at or under 12'0" wide, 13'6" high, 200' long: 24/7 with one extra civilian escort during darkness. Anything larger is daylight only. Conditions on your permit face override this.
- Weekend travel
At or under 14'6" wide, 15'0" high, 200' long: 7 days a week in daylight. Over that up to 16'0" wide or 17'0" high: Mon-Fri daylight plus Saturday until noon. Over 16'0" wide, over 17'0" high, or over 200' long: Mon-Fri only, no Saturday or Sunday movement.
- Holiday restrictions
No movement on New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving or Christmas, and none after noon on the day before a holiday or holiday weekend. IDOT posts dated restrictions and cutoff times each year under Announcements on ITAP; check before booking.
- Urban restrictions
Cook County expressways bar loads over 12'0" wide, 13'6" high or 120,000 lbs, with four exempt corridors. Over 14'6" to 16'0" wide moves only 9 a.m. to 3 p.m. Mon-Fri in Cook, DuPage, Lake, Kane, Madison, McHenry, Monroe, St. Clair and Will. Chicago needs a city permit.
Signage Illinois expects
- Oversize load sign
OVERSIZE LOAD signs are mandatory on the front and rear of the vehicle for loads over 10'0" wide, 14'6" high or 75' long, and on escort vehicles. Yellow sign about 7 feet by 18 inches, 12-inch black letters with 2-inch stroke; minimum 10-inch letters, 1.41-inch stroke.
- Flags
Clean red flags not less than 18 inches square must mark the extremities of all oversize vehicles, vehicle combinations and loads, and every protruding object.
- Beacons
All loads moving under oversize or overweight permit authority must display an operable oscillating, rotating or flashing amber light; add one at the rear if the load blocks it. Objects over 80' long need two, one over the cab and one within 10' of the rear.
Illinois permit office
The permit office is the authority on every number on this page. Call it, or open the official site, before you rely on a threshold for a load that is close to a line.
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What are the legal limits in Illinois without an oversize or overweight permit?
In Illinois, the legal limits without an oversize or overweight permit are 8'6" wide, 13'6" high, 53'0" long (semitrailer) and 80,000 lbs gross. Legal overhang is 3'0" front and 4'0" rear. Anything over those figures needs a permit from the Illinois permit office before it moves.
When does an oversize load need an escort or pilot car in Illinois?
On 2-lane roads in Illinois, escorts begin at 14'7" wide. On multi-lane roads, escorts begin at 14'7" wide. The first escort tier is "Front escort" at 14'7" – 16' wide. Every tier on this page quotes its rule and source.
Can oversize loads travel at night, on weekends or on holidays in Illinois?
Night travel: Permitted for some loads. Overweight-only at legal dimensions: 24/7. Oversize at or under 12'0" wide, 13'6" high, 200' long: 24/7 with one extra civilian escort during darkness. Anything larger is daylight only. Conditions on your permit face override this. Weekend travel: At or under 14'6" wide, 15'0" high, 200' long: 7 days a week in daylight. Over that up to 16'0" wide or 17'0" high: Mon-Fri daylight plus Saturday until noon. Over 16'0" wide, over 17'0" high, or over 200' long: Mon-Fri only, no Saturday or Sunday movement. Holidays: No movement on New Year's Day, Memorial Day, Independence Day, Labor Day, Thanksgiving or Christmas, and none after noon on the day before a holiday or holiday weekend. IDOT posts dated restrictions and cutoff times each year under Announcements on ITAP; check before booking.