Illinois vs Missouri Oversize Load Rules
What changes for an oversize load between Illinois and Missouri: legal height, pilot car triggers, height poles and travel hours.
I-70, reviewed October 2026
What changes at the Illinois and Missouri border
- Legal height
- Missouri allows 14 ft 0 in without a permit; Illinois stops at 13 ft 6 in. A load between the two is legal in Missouri and needs a permit in Illinois.
- First pilot car
- Missouri requires a pilot car from 12 ft 6 in wide; Illinois waits until 14 ft 6 in. A load between those widths needs an escort in Missouri only.
- Height pole
- Missouri sets a height-pole trigger at 15 ft 6 in; Illinois does not publish one, so check the permit.
Check one load against both states
Illinois
- Oversize permit required
- No width escort
Missouri
- Oversize permit required
- No width escort
11 ft 0 in wide, 14 ft 0 in tall. Length is not checked here.
Side by side
| Rule | Illinois | Missouri |
|---|---|---|
| Legal width | 8 ft 6 in | 8 ft 6 in |
| Legal height | 13 ft 6 in | 14 ft 0 in |
| Legal length | Semitrailer 53 ft on Class I/II designated highways; single truck 42 ft; tractor-semitrailer overall 65 ft on non-designated highways (no overall limit on Class I/II); doubles 28.5 ft per trailer on Class I/II (IDOT OPER 753). | Trailer and load 53 ft; truck-trailer combination 65 ft; auto/boat transporter 75 ft (80 ft stinger-steered) plus overhangs; towed units 65 ft; single units 45 ft. Tractor-semitrailer overall limit not clearly stated. |
| Gross weight | 80,000 lbs | 80,000 lbs |
| First pilot car at | 14 ft 6 in | 12 ft 6 in |
| Second pilot car at | Not confirmed | 16 ft 0 in |
| Height pole at | Not confirmed | 15 ft 6 in |
| Length escort at | 110 ft 0 in | 125 ft 0 in |
| Travel hours | Legal-size overweight: 24/7. Up to 12 ft wide, 13'6" high, 200 ft long: 24/7 (extra civilian escort at night). Up to 14'6" wide, 15 ft high, 200 ft long: 1/2 hr before sunrise to 1/2 hr after sunset, 7 days. Up to 16 ft wide, 17 ft high: sunrise-sunset Mon-Fri and until noon Saturday. Wider/taller than 16/17 ft: 9 am to 3 pm Mon-Fri. | One-half hour before sunrise to one-half hour after sunset. Night movement allowed for loads up to 12 ft 6 in wide, legal height and up to 110 ft long. Mon-Fri curfews in St. Louis, St. Charles, Kansas City and Springfield metro (about 6:30-9:00 a.m. and 3:30-6:30 p.m.; KC and Springfield 7-9 a.m. and 4-6 p.m.). |
| Weekends | Loads up to 14'6" wide/15 ft high move 7 days a week in daylight; up to 16 ft wide/17 ft high Saturday until noon only; loads over 200 ft long or over 16 ft wide/17 ft high have no Saturday or Sunday movement unless the permit says otherwise. | Since March 31, 2025 loads up to 16 ft wide may travel on weekends. No Saturday/Sunday movement in Lake of the Ozarks (May 25-Labor Day) and Branson (May 1-Nov 30) areas. |
| Trip permit | Fee not confirmed | $10.00 |
| Permit office | (217) 785-1477 (IDOT Bureau of Operations, Permit Office) | 1-866-831-6277 (MoDOT Motor Carrier Services) |
Go deeper
- Pilot car detail: Illinois, Missouri
- Full guides: Illinois, Missouri
- Running through both without local plates? Estimate the trip permit cost
- Moving over a holiday? Check holiday restrictions
Illinois and Missouri FAQs
- Do Illinois and Missouri require pilot cars at the same width?
- Missouri requires a pilot car from 12 ft 6 in wide; Illinois waits until 14 ft 6 in. A load between those widths needs an escort in Missouri only.
- Is the legal truck height the same in Illinois and Missouri?
- Missouri allows 14 ft 0 in without a permit; Illinois stops at 13 ft 6 in. A load between the two is legal in Missouri and needs a permit in Illinois.
- Do I need a separate permit for each state between Illinois and Missouri?
- Yes. Oversize and overweight permits are issued by each state, so a move through both needs a permit from IDOT Bureau of Operations, Permit Office and one from MoDOT Motor Carrier Services, each with its own route, hours and escort conditions.
- Which travel hours apply in Illinois and Missouri?
- Illinois: Legal-size overweight: 24/7. Up to 12 ft wide, 13'6" high, 200 ft long: 24/7 (extra civilian escort at night). Up to 14'6" wide, 15 ft high, 200 ft long: 1/2 hr before sunrise to 1/2 hr after sunset, 7 days. Up to 16 ft wide, 17 ft high: sunrise-sunset Mon-Fri and until noon Saturday. Wider/taller than 16/17 ft: 9 am to 3 pm Mon-Fri. Missouri: One-half hour before sunrise to one-half hour after sunset. Night movement allowed for loads up to 12 ft 6 in wide, legal height and up to 110 ft long. Mon-Fri curfews in St. Louis, St. Charles, Kansas City and Springfield metro (about 6:30-9:00 a.m. and 3:30-6:30 p.m.; KC and Springfield 7-9 a.m. and 4-6 p.m.). The conditions printed on the permit control.
Compiled from each state's published permit rules, reviewed October 2026. Not legal advice; the conditions printed on your permit control.