State Oversize Permits & Escorts Information


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Colorado DOT Phone Number: (303) 757-9539

DOT Website

PERMITS: Colorado oversize permits are valid for five days.

OPERATING TIME: Sunrise to Sunset. Up to 12′ wide, night travel is allowed with proper lighting (see Signs, Flags, & Lights, below). Over 12′ wide but not over 14′ wide requires an escort for night running.

RESTRICTED TRAVEL: Curfew times are shown on the addendum that accompanies an oversize permit. Eisenhower Tunnel on I-70: maximum overall height allowed is 13′-11″. Higher loads use US6 to bypass the tunnel. Over 11′ wide permitted loads must pull over and call to get clearance to pass through tunnel, but wider loads can use it. Loads into or out of Denver require a city permit for city streets, but Denver is very slow in turning them around (average 2-3 days).

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Length: 57′-4″ trailer & load legal on interstate or designated highways.


  • 4′ front
  • 10′ rear
  • Over 4′ rear needs lighting for night running (see Signs, Flags, & Lights, below)

Width: 8′-6″


  • 14′-6″ designated highways
  • 13′ non-designated


  • 80,000 Gross on Interstate
  • 85,000 on non-Interstate
  • Steer – 20,000
  • Single – 20,000
  • Tandem – 36,000
  • Tridem – 54,000

Length: 130′ (four-lane highways).

Width: 17′

Height: 16′

  • Over 14′-6″ requires a survey


  • Single – 22,000-27,000
  • Tandem – 42,000-50,000
  • Tridem – 55,000-65,000
  • Quad – 60,000-72,000

Maximum permitted weights depend on route classification and axle spacings.

Loads exceeding 17′ wide or 200,000 GVW are Super Loads and require 6-10 days for approval.



  • Over 85′ on some portions of two and four-lane highways – one escort
  • Over 110′ on two-lane or over 115′ on four or more lanes – one escort

Overhang: Over 25′ – one escort.


Interstate over 13′ – one rear escort or one flashing yellow light in rear.

The following requirements apply to most routes (“Green Routes”); some smaller routes may require more:

Two-lane highways:


  • over 13′ – one escort or one flashing yellow light in rear.
  • over 15′ – two escorts
  • or 1 front escort and flashing yellow light in rear.

Four-lane highways:


  • over 13′ – one rear escort or one flashing yellow light in rear
  • over 15′ – two escorts, or front escort and flashing yellow light in rear


  • Over 16′ – one escort with high pole
  • Over 17′-6″ – route survey and utility clearance letters also required

Note: All pilot car vehicles must be over 60″ wide for CO.

MISCELLANEOUS: Dozer blade can be detached and hauled with the dozer on same trailer if the load would be overweight with or without the blade. Colorado Chain Law: All commercial vehicle truck-tractors operating on I-70 between Dotsero (milepost 133) and Morrison (milepost 259) between September 1st to May 31st must carry sufficient chains to be in compliance with the Colorado chain law. You can be fined for failure to comply. A permit is now available for overweight divisible loads on tractor/trailers with tandem, tridem or quad trailer.

SIGNS, FLAGS & LIGHTS: “Oversize Load” signs are required front and rear for all oversize loads. They are not required and should not be used for overweight only loads. Flags are required at all four corners of any extremities for wide and over length loads, and at the end of load projections greater than 4 feet.

For night travel of wide loads, a flashing yellow light mounted on front of the vehicle and two or three mounted to the extreme rear are required. Over length or with rear overhang (over 10′) may run at night with a flashing yellow light mounted to front of vehicle and from one to three cluster lights mounted to overhang (red for rear overhang, yellow for front overhang). For night travel with legal overhang (10′ rear or less) but greater than 4′ rear, a red light or lantern plainly visible for 500 feet is required at the end of load projection.

Important Notice:
The following is provided for informational purposes only. We do not procure or arrange permits on behalf of carriers or discuss permit and escort requirements for particular shipments. The following links provide general guidelines for oversize permits and escorts for heavy haul shipping by state/province. State regulations are subject to change; If you find inaccurate information, please let us know, and we will update the page accordingly.