Colorado Truck Weight and Size Limits
Legal limits for a truck in Colorado without a permit: Interstate axle and gross weights, height, width, and semitrailer length, each with its official source.
Colorado limits at a glance
Interstate weight limits
Federal law sets the Interstate limits at 20,000 lb on a single axle, 34,000 lb on a tandem, and 80,000 lb gross, with the bridge formula on every axle group (23 CFR 658.17). States may keep higher limits they had before the federal limits took effect ("grandfather rights").
FHWA's Colorado summary lists a 36,000 lb tandem on Interstates, and its exceptions table lists the same grandfathered tandem limit.
Grandfathered: up to 110,000 lb GVW and 36,000 lb tandems on parts of I-25, I-70, I-76, I-225, and I-270.
FHWA on Colorado: Colorado has a grandfather provision under Federal law (23 CFR Part 658, Appendix C) to allow vehicles to operate up to 110,000 lbs. GVW and 36,000 lbs. on a tandem axle on parts of the Interstate system. See the Routes section for a full description of the routes to which this grandfather provision applies.
Bridge formula check with Colorado limits
A 5-axle tractor-trailer is filled in. Change the spacings and weights to match your rig; the limits for single axles, tandems, and gross are Colorado's Interstate limits.
Your result
Colorado limits off the Interstate
FHWA's summary of Colorado law for trucks in regular operation (no permit), including non-Interstate highways. It reflects state law as of October 1, 2012; check the state for later changes.
- Single axle
- 20,000 lbs.
- Tandem axle
- 36,000 lbs. on Interstates / 40,000 lbs. on non-Interstate highways
- Tridem axle
- Per FBF
- Gross weight
- Interstates: 80,000 lbs. and FBF* / Non-Interstate highways: 85,000 lbs. and State bridge formula**
- Other
- 500 lbs. per inch of tire width
Where Colorado allows more than federal limits
- Colorado weight limits for tandem axles-40,000 lbs. on non-Interstate highways-exceed the Federal limit of 34,000 lbs.
- Colorado allows a gross vehicle weight of up to 85,000 lbs. on non-Interstate highways.
- Alternative fuel vehicles are allowed an additional 1,000 lbs. of gross vehicle weight on non-Interstate highways.
Height, width, and length
- Width: 102 inches. States may not set a width limit of more or less than 102 inches on the National Network (23 CFR 658.15(a)). Permits can allow wider loads.
- Height: 14 ft 6 in. There is no federal height limit; each state sets its own.
- Semitrailer length: No separate semitrailer length for a laden combination: a laden tractor-semitrailer may not exceed 75 ft overall; an unladen one is exempt from the 70-ft combination limit if the semitrailer is 57 ft 4 in or less
- Grandfathered semitrailer length: 57 ft 4 in. The minimum semitrailer length the state must allow in a tractor-semitrailer combination on the National Network, based on lengths legal in the state on December 1, 1982. Federal law also requires at least 48 ft (23 CFR 658.13(b)(1)).
Over these limits you need a permit. Colorado oversize/overweight permits (800-350-3765).
Colorado compared with neighboring states
| State | Gross | Single | Tandem | Height | Semitrailer |
|---|---|---|---|---|---|
| Colorado | 80,000 lb | 20,000 lb | 36,000 lb | 14 ft 6 in | No separate semitrailer length for a l… |
| Arizona | 80,000 lb | 20,000 lb | 34,000 lb | 13 ft 6 in | 57 ft 6 in |
| Kansas | 80,000 lb | 20,000 lb | 34,000 lb | 14 ft | 59 ft 6 in |
| Nebraska | 80,000 lb | 20,000 lb | 34,000 lb | 14 ft 6 in | 53 ft including load |
| New Mexico | 86,400 lb | 21,600 lb | 34,200 lb | Pending | Pending |
| Oklahoma | 80,000 lb | 20,000 lb | 34,000 lb | 13 ft 6 in | Pending |
Sources
Source: FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendices A and B · Effective Oct 1, 2012 · Last verified Sep 28, 2026
Source: FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendix A: Colorado · Effective Oct 1, 2012 · Last verified Sep 28, 2026
Source: 23 CFR 658.15, Width (eCFR) · Last verified Sep 28, 2026
Source: 23 CFR part 658, Appendix B, Grandfathered Semitrailer Lengths (eCFR) · Last verified Sep 28, 2026
Source: Colo. Rev. Stat. § 42-4-504(4), (4.5)(b) (2024 printout) · Last verified Sep 28, 2026
Source: FHWA, Oversize/Overweight Load Permits: State permit contacts · Last verified Sep 28, 2026
Limits change, and cities, counties, and posted bridges can set lower ones. Check with Colorado before you run a load near the limits. Page data last verified Sep 28, 2026.