Alabama Truck Weight and Size Limits
Legal limits for a truck in Alabama 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/alabama
Alabama limits at a glance
| Limit | Alabama | Source |
|---|---|---|
| Interstate gross weight | 80,000 lb | 23 CFR 658.17, Weight (eCFR) |
| Interstate single axle | 20,000 lb | 23 CFR 658.17, Weight (eCFR) |
| Interstate tandem axle | 34,000 lb | 23 CFR 658.17, Weight (eCFR) |
| Width (National Network) | 102 in | 23 CFR 658.15, Width (eCFR) |
| Height | Pending verification | FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendix A: Alabama |
| Semitrailer length | Pending verification | FHWA, Compilation of Existing State Truck Size and Weight Limit Laws (Report to Congress, May 2015), Appendix A: Alabama |
| Grandfathered semitrailer length | 53 ft 6 in | 23 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").
Bridge formula check with Alabama 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 Alabama's Interstate limits.
Your result
Alabama limits off the Interstate
FHWA's summary of Alabama 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. on Interstate highways 36,000 lbs. on non-Interstate highways
- Tridem axle
- 42,000 lbs.
- Gross weight
- 80,000 lbs. on Interstate highways 84,000 lbs. (6 or more axles) on non-Interstate highways
- Other
- 10 percent scale or enforcement tolerance on non-Interstate highways
Where Alabama allows more than federal limits
- The State bridge formula allows up to 36,000 lbs. on tandem axles on non-Interstate highways, depending on axle spacing.
- The State bridge formula allows 42,000 lbs. on a tridem axle on non-Interstate highways.
- The State bridge formula allows a gross weight of 84,000 lbs. on a six axle truck-semitrailer (TST) combination.
- State law provides for a10 percent weight tolerance for enforcement on non-Interstate highways.
- State law exempts vehicles transporting certain commodities from State weight limits.
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: pending verification. There is no federal height limit; each state sets its own.
- Semitrailer length: pending verification.
- Grandfathered semitrailer length: 53 ft 6 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. Alabama oversize/overweight permits (800-499-2782).
Alabama compared with neighboring states
| State | Gross | Single | Tandem | Height | Semitrailer |
|---|---|---|---|---|---|
| Alabama | 80,000 lb | 20,000 lb | 34,000 lb | Pending | Pending |
| Florida | 80,000 lb | Pending | Pending | 13 ft 6 in | 48 ft |
| Georgia | 80,000 lb | 20,340 lb | 34,000 lb | 13 ft 6 in | 53 ft |
| Mississippi | 80,000 lb | 20,000 lb | 34,000 lb | Pending | Pending |
| Tennessee | 80,000 lb | 20,000 lb | 34,000 lb | Pending | Pending |
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: Alabama · 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: 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 Alabama before you run a load near the limits. Page data last verified Sep 28, 2026.