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Updated June 2026Canadian axle weight limits overview
Canada's road network is managed by a patchwork of federal, provincial, and municipal authorities, each with their own weight regulations. There is no single national axle weight standard — each province sets its own limits based on the capacity of its road infrastructure. However, the federal Memorandum of Understanding on Interprovincial Weights and Dimensions (MOU) provides standardized limits for commercial vehicles travelling between provinces.
Axle weight limits exist to protect road surfaces and bridges from damage caused by heavy vehicles. The relationship between vehicle weight and road damage is highly non-linear — doubling the axle weight causes approximately 16 times the pavement damage (the fourth-power law). This is why even modest overloads cause disproportionate infrastructure damage and carry significant fines.
Understanding the applicable limits for your specific province, route, and vehicle configuration is essential for legal operation and cost control. Overweight fines in Canada can exceed the value of the load being carried.
How axle groups work
Axle weight limits apply not to individual wheels but to defined axle groups. The definitions are consistent across most Canadian provinces:
- Single axle: One axle — a steer axle, a single drive axle, or a single trailer axle
- Tandem axle group: Two axles spaced within 1.2 metres of each other (most common rear drive axle configuration)
- Tridem axle group: Three axles spaced within 2.4 metres (common on B-train trailers)
- Quad axle group: Four axles within a defined spacing — less common, used on specialized heavy haulers
The group limits are higher than individual axle limits because weight is distributed over more tire contact points, reducing the load per unit of pavement area. However, group limits are not simply multiples of single axle limits — they reflect the dynamics of load distribution and pavement stress patterns.
Spring weight restrictions explained
Spring weight restrictions (spring break-up or spring thaw restrictions) are temporary reductions to normal axle weight limits applied during the spring thaw period. In most Canadian provinces, this is approximately February/March through April/May — the dates vary by province and year based on actual thaw conditions.
During freeze-thaw cycles, water in the road base expands as it freezes and contracts as it thaws. When saturated subgrade soil thaws from the top down, the lower layers remain frozen, trapping water in the upper layers and creating a saturated, weakened road base. Even standard legal loads can cause severe rutting and structural pavement failure under these conditions.
Spring restrictions are typically expressed as a percentage of the normal limit. British Columbia applies one of the strictest reductions at 75% of normal weight. Ontario applies 90%. Some provinces restrict specific road classes more aggressively than the provincial highway network.
Violating spring restrictions carries the most severe fines in the trucking regulatory framework — provinces specifically need to deter overweight operation during the period when roads are most vulnerable.
Province-by-province breakdown
Ontario: Single 10,000 kg, tandem 18,000 kg, tridem 24,000 kg, quad 27,500 kg. Spring restrictions March 1–April 30 at 90%. Regulated under O. Reg. 413/05 of the Highway Traffic Act.
British Columbia: Single 9,100 kg, tandem 15,400 kg, tridem 21,000 kg. Spring restrictions approximately March–May at 75%. Regulated under the Commercial Transport Act.
Alberta: Single 10,000 kg, tandem 17,000 kg, tridem 24,000 kg. Spring restrictions at 90%. Regulated under the Traffic Safety Act Vehicle Weights and Dimensions Regulation.
Quebec: Single 10,000 kg, tandem 18,000 kg, tridem 24,000 kg. Spring restrictions at 85%. Regulated under the Highway Safety Code.
Manitoba: Single 9,000 kg, tandem 17,000 kg, tridem 21,500 kg. Spring restrictions at 80%.
Saskatchewan: Single 9,000 kg, tandem 16,000 kg, tridem 21,500 kg. Spring restrictions at 75% — among the most restrictive in Canada.
Worked examples
Example 1 — Standard tandem drive tractor in Ontario:
- Steer axle: 7,700 kg (below 10,000 kg single limit ✓)
- Tandem drive axles: 17,000 kg (below 18,000 kg tandem limit ✓)
- Trailer tandem: 17,000 kg (below 18,000 kg ✓)
- Total vehicle weight: 7,700 + 17,000 + 17,000 = 41,700 kg (below 63,500 kg GVW limit ✓)
- Result: Legal in Ontario under normal season limits
Example 2 — Same truck during Ontario spring restrictions:
- Spring limit = 90% of normal
- Tandem drive limit: 18,000 × 0.90 = 16,200 kg
- Tandem drive axles at 17,000 kg: 800 kg over the spring limit
- Result: Must reduce payload by at least 1,600 kg total during spring restrictions
Axle weight limits by province
| Province | Single (kg) | Tandem (kg) | Tridem (kg) | Spring reduction |
|---|---|---|---|---|
| Ontario | 10,000 | 18,000 | 24,000 | 90% (Mar–Apr) |
| Quebec | 10,000 | 18,000 | 24,000 | 85% |
| British Columbia | 9,100 | 15,400 | 21,000 | 75% (Mar–May) |
| Alberta | 10,000 | 17,000 | 24,000 | 90% |
| Manitoba | 9,000 | 17,000 | 21,500 | 80% |
| Saskatchewan | 9,000 | 16,000 | 21,500 | 75% |
| Nova Scotia | 9,000 | 18,000 | 22,000 | 90% |
| New Brunswick | 9,000 | 18,000 | 24,000 | 85% |
| PEI | 9,000 | 18,000 | 22,000 | Various |
| Newfoundland | 9,000 | 18,000 | 24,000 | 90% |
Frequently asked questions
What are the axle weight limits in Ontario?
Under O. Reg. 413/05 of Ontario's Highway Traffic Act: single axle 10,000 kg, tandem axle group 18,000 kg, tridem axle group 24,000 kg, quad axle group 27,500 kg. Spring restrictions apply March 1 – April 30 at 90% of normal limits. Overweight charges in Ontario can exceed $5,000 for significant violations.
What are the axle weight limits in British Columbia?
Under BC's Commercial Transport Act: single axle 9,100 kg, tandem axle 15,400 kg, tridem axle 21,000 kg. BC applies one of the stricter spring restriction reductions — 75% of normal limits, typically March through May. BC also has specific requirements for oversize/overweight permits for loads exceeding these limits.
What is a spring weight restriction in Canada?
Spring weight restrictions (also called spring break-up restrictions) are temporary reduced weight limits applied to roads during the spring thaw period — typically February through May depending on the province. During freeze-thaw cycles, road bases become saturated and weakened, unable to support full legal weight. Violating spring restrictions results in heavy fines and can result in licence suspensions for repeat offenders.
What is the difference between a tandem and tridem axle?
A tandem axle group consists of two axles within 1.2 metres of each other. A tridem axle group consists of three axles within 2.4 metres of each other. The group limits are higher than individual axle limits because the weight is spread over more wheel contact points. A B-train can have both tandem and tridem axle groups on the same vehicle combination.
Do interprovincial weight limits differ from provincial limits?
Yes. The Memorandum of Understanding on Interprovincial Weights and Dimensions (MOU) sets standardized limits for vehicles travelling across provincial borders. These are sometimes lower than what individual provinces allow for intra-provincial travel. Check Transport Canada's commercial vehicle regulations for the current MOU limits before planning interprovincial routes.
What happens if I exceed axle weight limits in Canada?
Overweight violations in Canada result in fines that scale with the amount of excess weight. In Ontario, fines start around $300 for minor overages and escalate to $5,000+ for significant violations. In BC, fines of $10,000+ are possible for large overages. Repeat violations can result in vehicle impoundment, licence suspension, and CVOR abstract entries that affect future operating licences.
Are the axle weight limits different on secondary highways?
Yes. Many provinces apply lower weight limits on secondary highways, resource roads, and municipal roads compared to primary provincial highways. Seasonal restrictions on secondary roads may also start earlier and end later than those on primary routes. Check with the provincial transportation ministry and local municipalities for specific road restrictions on your planned route.
What is a CVSE permit for overweight loads in Canada?
Commercial Vehicle Safety and Enforcement (CVSE) or equivalent provincial authorities issue overweight permits for loads that exceed standard axle limits. These permits specify the allowed route, time of travel, escort requirements, and additional fees. Common permitted loads include heavy equipment, modular homes, and industrial machinery that cannot be disassembled to meet standard limits.
Regulation references
| Province | Regulation |
|---|---|
| Ontario | O. Reg. 413/05 — Highway Traffic Act |
| British Columbia | Commercial Transport Act, B.C. Reg. 30/78 |
| Alberta | Traffic Safety Act — Vehicle Weights and Dimensions Regulation |
| Quebec | Highway Safety Code (Code de la sécurité routière) |
| Manitoba | Highway Traffic Act — Vehicle Weights Regulation |
| Saskatchewan | Vehicle Weight and Dimension Regulations |
| Federal (interprovincial) | Transport Canada MOU on Interprovincial Weights and Dimensions |