Colorado Oversize and Overweight Trucking Regulations

Operating oversize or overweight (OS/OW) loads in Colorado requires strict adherence to the Colorado Department of Transportation (CDOT) regulations, specifically the Rules and Regulations of the Colorado Department of Transportation for Transport Permits for the Movement of Extra-Legal Vehicles or Loads (2 CCR 601-4). Carriers must obtain a permit whenever a vehicle or load exceeds standard legal dimensions: a total width of 8 feet 6 inches, a height of 13 feet, or a total length of 75 feet for a tractor-trailer combination. Weight limits are generally capped at 80,000 pounds Gross Vehicle Weight (GVW) without a permit, subject to the Federal Bridge Formula. Colorado classifies permits into several categories, including single-trip, annual, and special mobile equipment permits. Fees vary significantly based on weight and duration, ranging from $15 for a basic single-trip oversize permit to over $400 for annual overweight permits. DispatchTool assists carriers by integrating state-specific bridge clearances and weight restrictions into its truck-safe routing engine, ensuring drivers avoid restricted routes like the Eisenhower-Johnson Memorial Tunnels when carrying hazardous materials or exceeding height limits. Create a DispatchTool account to manage your permits and route planning in one interface.

Standard Legal Dimensions and Weight Limits

Before applying for a permit, carriers must verify if their load exceeds Colorado's legal limits. The maximum legal width is 8 feet 6 inches on all highways. The maximum legal height is 13 feet statewide, which is lower than the 13 feet 6 inches found in many eastern states. Length limits vary by configuration; a single unit is limited to 45 feet, while a tractor-semi-trailer combination is generally limited to a 57-foot 6-inch trailer provided the total wheelbase remains within safe operating parameters. Weight is governed by the Bridge Formula, with a maximum of 20,000 pounds per single axle and 34,000 pounds per tandem axle group. Exceeding any of these metrics necessitates a CDOT Extra-Legal permit.

Permit Types and Associated Fees

CDOT offers multiple permit structures depending on the frequency of the move. A Single Trip Permit is valid for 5 days and costs $15 for oversize-only loads. For overweight loads, the fee increases based on the weight: $15 plus $5 per axle for loads up to 200,000 pounds. Annual permits are available for $250 for oversize loads and $400 for overweight loads, provided the vehicle does not exceed 17 feet in width, 16 feet in height, or 110 feet in length. Special 'LVC' (Longer Vehicle Combination) permits are required for Rocky Mountain Doubles or Triple trailers, which are subject to specific corridor restrictions on I-70 and I-25.

Pilot Car and Escort Requirements

Escort requirements in Colorado are determined by the dimensions of the load and the type of highway being traversed. For loads exceeding 13 feet in width on a two-lane highway, one front pilot car is mandatory. If the width exceeds 15 feet, two escorts (front and rear) are required. For height, any load exceeding 16 feet must have a lead escort equipped with a high-clearance pole. Length also triggers escort needs: loads over 85 feet on two-lane roads or over 110 feet on multi-lane highways require a rear escort. Pilot car operators must be certified, and vehicles must be equipped with 'Oversize Load' signs and amber flashing lights visible from 500 feet.

Mountainous Terrain and Tunnel Restrictions

Colorado’s geography introduces specific restrictions, most notably at the Eisenhower-Johnson Memorial Tunnels (EJMT) on I-70. The maximum height allowed through the EJMT is 13 feet 11 inches; any load taller must exit at US 6 (Loveland Pass). Furthermore, loads exceeding 11 feet in width are restricted to passing through the tunnels only during specific off-peak hours, often between 11:00 PM and 6:00 AM, and require coordination with tunnel officials. During winter months, typically September 1 through May 31, all commercial vehicles traveling on I-70 between Mile Marker 133 (Dotsero) and Mile Marker 259 (Morrison) must carry tire chains, regardless of weather conditions at the time of entry.

Curfew and Holiday Travel Restrictions

Oversize loads are generally prohibited from traveling during holiday periods, including New Year’s Day, Memorial Day, Independence Day, Labor Day, Thanksgiving, and Christmas. In the Denver, Colorado Springs, and Pueblo metropolitan areas, 'Rush Hour' curfews apply. Movement is restricted Monday through Friday from 6:00 AM to 9:00 AM and from 3:00 PM to 6:00 PM for any load exceeding 12 feet in width. Night travel is permitted for loads that are only overweight (not oversize) or for loads that do not exceed 10 feet in width, provided they have proper lighting as defined by 49 CFR 393.11.

Superload Permitting Process

Colorado defines a 'Superload' as any vehicle or load that exceeds 200,000 pounds, 17 feet in width, or 16 feet in height. These applications undergo a rigorous Bridge Branch review which can take 5 to 10 business days. The applicant must provide a detailed axle spacing diagram and may be required to pay for a structural analysis if the route involves crossing specific weight-limited bridges. Fees for superloads include the base permit fee plus an hourly engineering review fee of approximately $50 per hour. The applicant is responsible for all costs associated with utility line moves or traffic signal rotations required along the route.

Sources

Colorado Department of Transportation (CDOT) Freight Office (2024) — https://www.codot.gov/business/permits/truckpermits Colorado Code of Regulations (2 CCR 601-4) (2024) — https://www.sos.state.co.us/CCR/GenerateRuleNav.do?ruleNext=Next&ruleId=2638 Colorado General Assembly - Statute 42-4-106 (2023) — https://leg.colorado.gov/sites/default/files/images/olls/crs2023-title-42.pdf

Frequently asked

What is the maximum weight allowed with a standard overweight permit in Colorado?

A standard single-trip overweight permit allows for a GVW of up to 200,000 pounds, depending on axle configurations and bridge capacities. Loads exceeding 200,000 pounds are classified as Superloads and require a separate engineering review.

Are there specific chain laws for oversize loads in Colorado?

Yes, under Colorado Revised Statute 42-4-106, all commercial vehicles with a GVWR of 16,001 pounds or more must carry chains when traveling on I-70 between September 1 and May 31. This applies to oversize loads, which may also face additional travel suspensions during Code 15 or Code 16 chain law activations.

When are 'Oversize Load' signs required?

Signs are required on the front and rear of the vehicle for any load exceeding 8 feet 6 inches in width or 75 feet in length. The signs must be at least 7 feet wide and 18 inches high with black letters on a yellow background.

How much does a Colorado single-trip oversize permit cost?

A single-trip permit for an oversize load (not overweight) costs $15.00 and is valid for a period of 5 days.

What are the Denver rush hour curfew times for wide loads?

Movement is prohibited for loads wider than 12 feet between 6:00 AM – 9:00 AM and 3:00 PM – 6:00 PM, Monday through Friday, within the Denver, Colorado Springs, and Pueblo urban areas.