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Utah Truck Weight and Size Limits

Legal limits for a truck in Utah without a permit: Interstate axle and gross weights, height, width, and semitrailer length, each with its official source.

Utah limits at a glance

Utah truck size and weight limits with sources
LimitUtahSource
Interstate gross weight80,000 lb23 CFR 658.17, Weight (eCFR)
Interstate single axle20,000 lb23 CFR 658.17, Weight (eCFR)
Interstate tandem axle34,000 lb23 CFR 658.17, Weight (eCFR)
Width (National Network)102 in23 CFR 658.15, Width (eCFR)
Height14 ftUtah DOT, Legal Height, Width, & Length
Semitrailer length53 ft (no overall length limit on a tractor-semitrailer when the trailer is 53 ft or less)Utah DOT, Legal Height, Width, & Length
Grandfathered semitrailer length48 ft23 CFR part 658, Appendix B, Grandfathered Semitrailer Lengths (eCFR)

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").

Grandfathered: up to 129,000 lb GVW on I-15, I-70, I-80, I-84, I-215, and UT-201.

FHWA on Utah: Utah has a grandfather provision under Federal law (23 CFR Part 658, Appendix C) to allow vehicles to operate up to 129,000 lbs. GVW 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 Utah 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 Utah's Interstate limits.

Axle spacings

Center of one axle to the center of the next, in feet. Axle 1 is the steer axle. 4 ft 6 in = 4.5.

Axle weights (optional)

From your scale ticket. Leave all blank to see the limits only.

Your result

Enter your axle spacings and tap "Check bridge formula". A 5-axle tractor-trailer is filled in.

Open the full bridge formula calculator →

Utah limits off the Interstate

FHWA's summary of Utah 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
34,000 lbs.
Gross weight
80,000 lbs.
Other
10,500 lbs. per wheel

Where Utah allows more than federal limits

Height, width, and length

Over these limits you need a permit. Utah oversize/overweight permits (801-965-4892).

Utah compared with neighboring states

Interstate weight limits, height, and semitrailer length. "Pending" means not yet verified.
StateGrossSingleTandemHeightSemitrailer
Utah80,000 lb20,000 lb34,000 lb14 ft53 ft
Arizona80,000 lb20,000 lb34,000 lb13 ft 6 in57 ft 6 in
Colorado80,000 lb20,000 lb36,000 lb14 ft 6 inNo separate semitrailer length for a l…
Idaho80,000 lb20,000 lb34,000 lb14 ft48 ft
Nevada80,000 lb20,000 lb34,000 lb14 ftPending
New Mexico86,400 lb21,600 lb34,200 lbPendingPending

Sources

Source: 23 CFR 658.17, Weight (eCFR) · Last verified Sep 28, 2026

Source: FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendix A: Utah · 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 B: Summary of State Exceptions to Federal Truck Weight Limits · 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: Utah DOT, Legal Height, Width, & Length · 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 Utah before you run a load near the limits. Page data last verified Sep 28, 2026.

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