Container’s Own Weight Limit
Every container door displays its maximum weight capacity, for example, "MAX GROSS: 30480KGS" — indicating the total weight of the container and its cargo must not exceed this figure. The tare weight is 2200KGS for 20GP containers, 3720-4200KGS for 40GP containers, and some HQ containers have a MAX GROSS of 32000KGS.
This limit represents the maximum strength the container body can endure. Overloading may lead to damages like body deformation, floor detachment, or roof beam bending, and the shipper will be fully liable for all resulting losses. Currently, most professional container terminals in China are equipped with automatic weighbridges, so any container exceeding the body weight limit will be rejected by terminals. It is advisable to check the weight limit on the container before loading to avoid unnecessary container return and reloading.
If the cargo is indeed overweight and cannot be split, overweight containers are an option. This will incur a weight selection fee. Normally, terminals or yards stack ordinary dry containers of shipping companies together. To pick out special heavy-duty containers (such as the 20GP heavy-duty ones mentioned earlier), terminals and yards have to search one by one, and the resulting selection fee is usually the same as the designated container fee.
Other Weight Limit Factors (Container Transportation Requires Multi-Department Collaboration)
1. Shipping Company Weight Restrictions
Each shipping company has its own weight policies, generally based on the principle of not damaging the container.
For balancing space and weight: Every container ship has fixed space and weight capacities, but these two are not always fully utilized in balance on a specific route. Conflicts often arise in North China, where heavy cargo is concentrated — the ship’s weight limit is reached while there is still plenty of space left. To make up for the space loss, shipping companies often adopt a surcharge strategy, i.e., charging extra freight when the cargo weight exceeds a certain tonnage.
For companies buying space from others: Shipping companies that do not use their own ships but purchase space from other carriers have stricter weight limits. This is because space transactions between shipping companies are usually calculated at 1TEU=14TONS or 16TONS, and overweight cargo is not allowed to be loaded.
During peak seasons (space shortage): Depending on the popularity of the route, shipping companies will lower the weight limit for each container type accordingly.
When booking space, you should ask the freight forwarder about the shipping company’s weight limit before shipment. If not confirmed in advance, there will be risks for heavy cargo. Some shipping companies will directly require the shipper to tow the cargo away, unload it, or reweigh it without any negotiation after overloading, and these costs are hard to control.
2. Port Area Weight Restrictions
It mainly depends on the load capacity of the machinery and equipment at terminals and yards.
After a container ship berths at the terminal, cranes are needed for loading and unloading, and then trucks transport the containers to the yard where forklifts unload them. If the container weight exceeds the equipment’s load capacity, it will cause difficulties in terminal and yard operations. Therefore, for small ports with outdated equipment, shipping companies usually inform the weight limit in advance and refuse overweight cargo.
3. Weight Limits for Feeder Vessels or Highways
Those who have handled U.S. inland points are well aware that U.S. highway transportation has very strict weight limits. Many containers are transported by trucks to inland areas after being unloaded at terminals, so highway weight limits also become a reason for shipping companies to restrict container weight (this does not apply to cargo only delivered to the terminal).
Cargo to the U.S. route has strict weight requirements, mainly affected by the highway weight limit for U.S. inland points. Generally, 20GP containers are limited to 17.3 tons and 40HQ containers to 19.5 tons, but different ports have different weight limits.
4. Route Weight Restrictions
For different routes, shipping companies arrange capacity based on the order of port calls, types of exported cargo, and route popularity. Combined with the load capacity of the destination port’s equipment, the weight limits for 20GP/40GP containers naturally vary across routes.
Solutions for Overweight Issues
Overweight issues are mainly categorized into port area overweight, shipping company overweight, and destination port overweight.
Shipping company overweight: Negotiate with the shipping company to pay the overweight surcharge, and proceed with the shipment as normal otherwise.
Port area overweight (with independent regulations): If overweight is detected when entering the port, negotiate with the port authority to pay the overweight fee plus labor fees, or unload and reload the cargo.
Destination port overweight: Generally, paying a fine can resolve the issue within a certain range. If the overweight is severe and the cranes along the route cannot bear the weight, the cargo can only be transshipped at nearby ports or returned to the origin.