Wisconsin OS/OD Overview
Permit Required
Yes – any vehicle/load exceeding legal dimensions or weight must obtain a permit from the Wisconsin Department of Transportation (WisDOT).
Legal Limits (Without Permit)
- Width: 8'6"
- Height: 13'6"
- Length: 75' (combo); 53' trailer allowed
- Weight: 80,000 lbs GVW (with standard axle limits)
Permitted Load Maximums (Typical Upper Limits)
- Width: Up to 16' with escorts
- Height: Over 15' requires route clearance and utility coordination
- Length: Over 130' with route review and escort
- Weight: Over 200,000 lbs requires engineering review and bridge analysis
Superloads require additional review time and coordination with WisDOT engineers and possibly law enforcement.
Travel Hours
- Standard: ½ hour before sunrise to ½ hour after sunset
- Weekend: Travel allowed until 12:00 PM Saturday; no travel on Sunday for most OS/OW loads
- Holidays: No travel on major holidays or after noon the previous weekday
- Night travel: May be approved for smaller loads (e.g. under 10' wide) with proper lighting
Escort Requirements (General Guidelines)
| Dimension | Escort Requirement |
|---|---|
| Width > 12' | 1 Escort (front on 2-lane, rear on multi-lane) |
| Width > 14' | 2 Escorts (front and rear) |
| Height > 15' | High pole escort and utility notification required |
| Length > 130' | 1 or more Escorts depending on load and route |
Additional Notes
- Loads must display “Oversize Load” signs, red/orange flags on extremities, and amber beacon lights
- Seasonal weight restrictions (“frost laws”) may apply in early spring—check before travel
- Permits are issued through the WisDOT Oversize/Overweight Permit System (WisPERMIT)
Detailed Information
PERMITS: Permits valid for five consecutive days. Must have permit prior to entering the state.
OPERATING TIME: Loads not exceeding 12' wide, 13'6" high or 150' long may run 24/7, except between 4:00PM to 8:00PM on Sunday, and between 4:00 P.M. to 8:00 P.M. between the fourth Sunday in May and Labor Day. Greater than these dimensions may not run during hours of darkness, not from Noon on Saturday until sunrise on Monday, and not between 4:00 P.M. to 8:00 P.M. between the fourth Sunday in May and Labor Day. Overweight only can travel 24/7, including weekends and holidays, unless otherwise stated on the permit.
RESTRICTED TRAVEL:
Travel is restricted on major holidays and holiday weekends, with some variations according to size.
LEGAL DIMENSIONS: Width: 8'6" Height: 13'6" Length: 53' semi-trailer on designated highways (provided kingpin to center of rear tandem or to center of last axle of a Tridem does not exceed 43'), 48' semi-trailer and 75' overall on other roads Overhang; 3’ front and 4’ rear. Weight: 80,000 Gross Single – 20,000 Tandem – 34,000 Tridem – 37,000
ROUTINE PERMIT LIMITS: Width: 16' Height: Depends on routes Length: No set limit Weight: Single – 20,000 (with 4 tires) Tandem – 65,000 Tridem – 81,000 Loads exceeding 16' or 150,000 pounds are considered as Super Loads. Quad - 90,000
ESCORTS: Width: Over 15' – 1 escort Height: Usually not required, depends on routes Length: Usually not required
SEASONAL LOAD (WEIGHT) RESTRICTIONS: Spring thaw overweight restrictions usually go into effect on
"Class 2 Roads" from approximately early March until mid-May. Interstates and US Highways are normally not restricted. The start date varies from year to year.
MISCELLANEOUS: Farm equipment delivered to a Wisconsin destination and not using any Interstate routes, does not need a permit, but can only run on Monday through Thursday and up to 2:00PM on Friday.
SIGNS, FLAGS & LIGHTS: "Oversize Load" signs required when vehicle/load exceeds 10' wide or is overlength. They must be lit up to run at night. Flags (18" square) are required at front and rear corners of overwidth loads, and at the widest point of any load which is more than 4" wider than the vehicle or the front or rear corners of the load. When overlength, a single flag shall be fastened at the extreme rear of the load if the overlength or projecting portion is 2' wide or less, or 2 flags if over 2' wide. Lighting rules for night moves are specified in the Wisconsin Permit General Provisions (MV2605) sheet.