Maine Truck Weight and Size Limits
Legal limits for a truck in Maine without a permit: Interstate axle and gross weights, height, width, and semitrailer length, each with its official source.
Data pending verification
Some official figures this page relies on haven't been confirmed against the source yet. Don't rely on results here until this notice is gone.
What's pending
- weight-limits/states/maine
Maine 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 on Maine: Maine has a grandfather provision under Federal law (23 CFR Part 127) to allow vehicles to operate up to 22,400 lbs. for a single axle, 41,000 lbs. for a tandem axle, 50,000 lbs. for a tridem axle, and 100,000 lbs. GVW on all Interstate and non-Interstate highways on the Maine Turnpike.
Bridge formula check with Maine 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 Maine's Interstate limits (federal limits stand in where a figure is pending).
Your result
Maine limits off the Interstate
FHWA's summary of Maine 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. on Interstates when GVW exceeds 73,280 / 22,400 lbs. on Interstates when GVW is less than 73,280 / 22,400 lbs. for a six-axle combination on interstate highways / 22,400 lbs. on non-Interstate highways
- Tandem axle
- 34,000 lbs. on Interstate highways / 38,000 lbs. on non-Interstate highways / 41,000 lbs. for six-axle combination on interstate and non-Interstate highways*
- Tridem axle
- 45,000 lbs. on Interstate highways / 48,000 lbs. on non-Interstate highways / 50,000 lbs. for a six-axle combination on interstate and non-Interstate highways†
- Gross weight
- 80,000 lbs. on Interstate highways / 94,000 lbs. for a four-axle SU truck in combination with a two-axle trailer on non-Interstate highways / 100,000 lbs. for a qualifying combination of a three-axle truck tractor and tri-axle semitrailer
- Other
- 600 lbs. per inch width of tire / 4 percent portable scale tolerance on Interstate highways
Where Maine allows more than federal limits
- Maine State statute allows for several axle and GVW exemptions for various types of commodities and vehicles.
- Certain commodities are allowed a 10 percent weight tolerance over State limits provided weight limits do not exceed 24,200 lbs. for a single axle, 46,000 lbs. for a tandem axle, 54,000 lbs. for a tridem axle, and 100,000 lbs. GVW.
- Certain vehicles carrying certain commodities to and from certain facilities across the Canadian border are allowed increased weight limits up to 137,700 lbs. on specific routes depending on the configuration.
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: 13 ft 6 in (structural height; the load may not extend more than 6 in above the maximum structural height). There is no federal height limit; each state sets its own.
- Semitrailer length: 48 ft on the Interstate and National Network; a semitrailer over 48 ft and up to 53 ft is allowed if the kingpin to the center of the rearmost axle is 45 ft 6 in or less and the other conditions of § 2390 are met
- Grandfathered semitrailer length: 48 ft. 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. Maine oversize/overweight permits (207-624-9000, extension 52134).
Maine compared with neighboring states
| State | Gross | Single | Tandem | Height | Semitrailer |
|---|---|---|---|---|---|
| Maine | Pending | Pending | Pending | 13 ft 6 in | 48 ft on the Interstate and National N… |
| New Hampshire | 80,000 lb | 20,000 lb | 34,000 lb | 13 ft 6 in | 53 ft |
| Vermont | 80,000 lb | Pending | Pending | 13 ft 6 in | 53 ft on the Interstate and qualifying… |
| Massachusetts | 80,000 lb | 22,400 lb | 34,000 lb | 13 ft 6 in | 53 ft |
Sources
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: FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendix A: Maine · 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: 29-A M.R.S. § 2390 · Last verified Sep 28, 2026
Source: 29-A M.R.S. § 2380 · 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 Maine before you run a load near the limits. Page data last verified Sep 28, 2026.