Verified Gross Mass (VGM): Rules, Methods and Common Errors

What VGM is and why it exists

Verified Gross Mass is the total weight of a packed container: the cargo, all packaging, all dunnage and securing material, plus the container's own tare weight. Under the SOLAS Convention it must be provided to the carrier and the terminal before a packed container can be loaded onto a vessel.

The requirement followed a series of incidents in which mis-declared container weights contributed to stack collapses, vessel stability problems, lifting failures and road accidents. A container declared at 12 tonnes and actually weighing 24 is not a paperwork problem — it is a stow plan built on false information.

The legal position is unambiguous: no VGM, no loading. Terminals will not load a container without one, and carriers will not accept the risk of doing so.

Who is responsible

The obligation rests on the shipper named on the Bill of Lading. Not the packer, not the haulier, not the forwarder — the named shipper, who must ensure the VGM is obtained, is accurate, is signed by an authorised person and reaches the carrier and terminal in time.

In practice the work is frequently delegated: the packing warehouse weighs, a forwarder submits. Delegation does not transfer the responsibility. If the declaration is wrong, the shipper named on the transport document answers for it.

The two permitted methods

Only two methods are permitted, and estimating is not one of them. Both require calibrated and certified equipment, and both require the result to be documented.

Where VGM goes wrong

Almost every VGM discrepancy traces to one of a handful of causes, and all of them are avoidable with a checklist at the packing point.

• Generic tare weight — tares vary by manufacturer, age and repair history by several hundred kilograms. Read the actual container's door
• Dunnage omitted — airbags, timber bracing, lashing and edge protection are cargo for VGM purposes and are routinely forgotten
• Pallets omitted — a pallet weighs 20 to 30 kg and twenty of them is half a tonne
• Packaging omitted — shrink wrap, strapping and internal packing all count
• Weighing before loading is finished, so the last few packages are missing
• Submitting against the booking rather than the specific container number
• Product weight taken from a specification rather than measured, on cargo with natural weight variation
• Method 2 used without an approved documented procedure, which makes the declaration non-compliant even if the number is right
• The declaration unsigned, or signed by someone not authorised to do so

Cut-offs and submission

VGM has its own cut-off, separate from the documentation cut-off and from the physical cargo cut-off. It is frequently the earliest of the three, and missing it is one of the more reliable ways to have a container rolled — because unlike a late document, there is no way for the carrier to work around a missing VGM.

Submission routes vary: carrier portals, EDI, port community systems and, on some trades, email. The declaration must identify the shipper, the container number, the VGM figure, the units and the method used, and it must carry the name or signature of an authorised person.

Cross-checking your own declaration

The container packing list is the natural check on a VGM. Your declared cargo weight plus the stencilled tare should approximate the weighbridge figure closely. When they diverge materially, something is wrong and finding out what is far cheaper before the container ships.

• A weighbridge figure well above the packing list usually means packaging, pallets or dunnage were omitted from the list
• A figure well below usually means cargo was not loaded, or was loaded into a different container
• A difference of a few hundred kilograms often means a generic tare was used instead of the actual one
• A difference that changes between weighings points at equipment calibration
• Any material difference should be resolved before the B/L is finalised, since the gross weight also appears there