Verified gross mass (VGM)

Since 1 July 2016, the SOLAS Convention has required the gross mass of every packed export container to be verified before it is loaded on a ship. The shipper named on the carrier's bill of lading or sea waybill is responsible for obtaining the VGM and submitting it, signed by an authorized person, to the carrier and terminal before the VGM cut-off. A container without a VGM must not be loaded.

SOLAS allows two methods. Method 1 weighs the packed and sealed container as a whole, for example on a calibrated weighbridge, with the truck and chassis deducted. Method 2 weighs all packages and cargo items, adds packing, dunnage and securing material, then adds the container's tare weight marked on it; it must follow a procedure certified or approved by the authority of the country where the packing took place. Estimating is not allowed under either method.

VGM is not the cargo weight on the booking or packing list. For example, 18,000 kg of cargo with 400 kg of pallets and lashing in a 40-foot container with a 3,750 kg tare gives a VGM of 22,150 kg. National authorities set their own tolerances between declared and checked weights, so a margin accepted in one country may be refused in another. When a forwarder appears as shipper on the master bill, the VGM obligation falls on the forwarder.