Quebec truck weight limits
Canadian weight limits are set provincially, harmonised by the interprovincial Memorandum of Understanding on Vehicle Weights and Dimensions: every province and territory accepts MOU-compliant vehicles on a designated highway network. Unlike the US, Canada has no federal bridge formula — axle-group limits and interaxle spacing govern instead, and everything is in kilograms.
MOU limits — tractor semitrailer (designated network)
| Axle group | Limit |
|---|---|
| Steering axle | 5,500 kg |
| Single axle | 9,100 kg |
| Tandem group (1.2–1.85 m spread) | 17,000 kg |
| Tridem group, 2.4–<3.0 m spread | 21,000 kg |
| Tridem group, 3.0–<3.6 m spread | 23,000 kg |
| Tridem group, 3.6–3.7 m spread | 24,000 kg |
| Gross — 5-axle (tandem semitrailer) | 39,500 kg |
| Gross — 6-axle (tridem semitrailer) | 43,500–46,500 kg by tridem spread |
Quebec-specific rules
- Quebec's normal-period limits are more generous than the MOU in places — e.g. tandem groups up to 18,000 kg (spread-dependent) under the Vehicle Load and Size Limits Regulation (CQLR c C-24.2, r 31).
- Spring thaw period is the big gotcha: from roughly mid-March to the end of May (three zones, dates published annually), limits drop below normal — tandems to ~15,500 kg. Loads legal in January can be illegal in April.
- Official reference: the MTQ Road Vehicle Load and Size Limits Guide; thaw dates on the Transports Québec site.
CA-QC (or CA-MOU for the interprovincial baseline) and the verdict applies Canadian limits in kg, including province advisories.US comparison
Crossing south? The US Interstate system uses 80,000 lb gross (≈36,287 kg), 34,000 lb (≈15,422 kg) tandems and the Federal Bridge Formula — stricter than the MOU on tandems and gross. A load that is legal here can be illegal at the border. See our US state guides and bridge formula explainer.
LoadLegit computes per-axle-group loads from your rig and load plan, applies MOU or province rules, and tells you the exact tandem slide when you're over.
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