What Is VGM? How Is the Verified Gross Mass Declared?

What VGM is and why it is mandatory

The real weight of every loaded container going to sea is measured and reported to the carrier and the terminal before it sails. This report is called VGM (Verified Gross Mass). What it measures is not the net weight of the goods but the container’s total weight on the ground, including everything inside it.

The requirement stems from SOLAS, the International Convention for the Safety of Life at Sea. The rule is the amendment made to SOLAS Chapter VI, Regulation 2, which entered into force on 1 July 2016; the implementation details are set out in IMO guideline MSC.1/Circ.1475. Since that date, a container is not loaded onto a ship without the shipper’s declaration. When the declaration is missing, the only way forward, where the national authority permits it, is to have the container weighed at the terminal — which also brings extra cost and delay.

The rule arose from a safety problem. When a ship is loaded, the stowage plan is built around the declared weights: heavy containers go low, light ones go high. The ship’s stability calculation, its lashing calculation and its crane capacity all rest on these figures. When the declaration departs from reality, the effect is not confined to a single container; it affects the whole bay, the ship’s stability, and handling at the port. Incorrect weight declarations are frequently cited as a contributing factor in accident investigations into stack collapses. The same figure is also useful on land: it shows whether the tractor unit leaving the port will exceed its total weight limit. Axle load, however, depends on how the cargo is distributed inside the container and on the vehicle configuration, so it cannot be derived directly from VGM and must be calculated separately.

Who is responsible

The party obliged to provide VGM is the party named as shipper on the bill of lading. This distinction is often overlooked in practice:

• The party responsible is not the warehouse, manufacturer or loading crew that physically packs the container, but the party named on the bill of lading.
• The Incoterms term does not determine responsibility. Whether the sale is FOB or CIF, the declaration is required from the shipper named on the bill of lading.
• If a forwarder issues its own house bill of lading, the shipper on that document is usually the seller; what matters is whose name appears on the document. Because the shipper on the carrier’s master bill of lading is the forwarder, the SOLAS declaration is required from the forwarder at the master level.
• The weighing itself can be outsourced to a service provider, but responsibility for the accuracy of the declaration cannot be delegated.

The declaration is signed in the name of a person authorised on behalf of the shipper. The IMO guideline provides that the signature may be electronic, and that the signatory’s name should be written in capital letters.

Two methods: weighing or adding up

SOLAS recognises two routes. Both are valid, but not every load suits both.

	Method 1	Method 2
What is done	The loaded container, doors closed, is weighed on a calibrated weighbridge	The weights of the cargo, packaging, pallets and securing material are added up, and the container’s tare is added on top
Where it is done	Weighbridge, terminal, port gate, factory scale	Loading point, warehouse, production facility
When it suits	Cargo that cannot be weighed piece by piece, or is bulk in character: scrap, used machinery, mixed consolidated cargo	Standard packaged cargo with documented unit weights: cartons, sacks, tins, palletised shipments
Weak point	Access to a weighbridge, queues and extra cost	Any forgotten item directly produces a wrong declaration
Regulatory condition	The weighing instrument must comply with weights-and-measures regulation, be stamped, and have valid calibration	The method used must be approved by the competent authority of the country where packing was completed

Method 2 cannot be used for loads whose pieces cannot be weighed individually: for scrap, bulk-natured material, and undocumented second-hand goods, Method 1 is the only option.

What goes into VGM: a worked example

The declared figure covers everything in the container at the moment of lifting: the net weight of the goods; packaging such as cartons, boxes, crates, sacks, stretch-wrap and tape; pallets, skids, wooden crates and blocking; dunnage boards, airbags, straps and corner protectors used for securing; and the container’s own tare.

The tare is shown in the weight markings block on the container door; among the MAX GROSS / TARE / NET lines, the one you want is TARE. The CSC plate (safety approval plate) does not show the tare — it shows the container’s maximum operating gross weight. On some containers the two pieces of information appear together on a combined data plate, but this is not the general rule. The tare should not be written from memory or from a type average; it varies between containers of the same type depending on manufacturer and repair history. Repairs such as a floor replacement can move the tare away from the value stamped on the unit; the only remedy for that is Method 1.

VGM cannot exceed the maximum gross weight shown on the CSC plate. If it turns out to exceed it, the container is unloaded and the cargo split — a delay that can push the plan back by days. Nothing is deducted from VGM: it is neither the net weight nor the container’s payload capacity.

Example: 18 pallets of cartoned product loaded into a 20-foot container (figures are illustrative).

Item	Weight
Net weight of the goods (18 × 800 kg)	14,400 kg
Carton, stretch-wrap, tape	396 kg
18 europallets	450 kg
Securing: blocking, airbags, straps	60 kg
Container tare (TARE line)	2,250 kg
VGM	17,556 kg

If the net weight from the invoice had been declared instead, the figure would have been 14,400 kg — a gap of 3,156 kg, roughly 18 percent of the true weight.

When and how the declaration is submitted

VGM has its own cut-off time. The reason is simple: the ship’s stowage plan is prepared using VGM data, and a figure arriving after the plan is closed has no place in it. This is a separate time from the documentation cut-off, and on most carriers it closes earlier; the applicable time is confirmed from the booking confirmation.

The declaration is transmitted through the carrier’s portal, a terminal system, an EDI message (VERMAS), or a form accepted by the carrier. The channel varies by carrier.

The declaration generally includes: the booking number, the container number, the VGM value and unit (kilograms), the method used (1 or 2), the name of the declaring company, and the capitalised name of the authorised signatory. If Method 1 was used, the weighbridge ticket should be kept — it is the supporting record if a dispute arises later. If anything is added to the container, or part of the load is removed, after the declaration is submitted, the declaration must be updated.

If no declaration is submitted, the outcome is a single sentence: the container is not loaded onto the ship. What follows depends on the situation:

• If the container has already entered the terminal, it waits there for the next sailing; terminal storage (called demurrage on some carriers) starts to run, while equipment detention generally stops once it has gated in
• If the container is still outside the terminal, the opposite applies: storage does not run, but detention keeps running
• Return of the empty container, re-weighing and late-declaration items get invoiced
• In a letter-of-credit transaction, missing the latest shipment date creates a document discrepancy
• If weighing at the terminal reveals a significant deviation from the declaration, restow costs and administrative sanctions can follow

The competent authority, regulation and tolerance in Türkiye

The authority applying the rule in Türkiye is the Ministry of Transport and Infrastructure, with the Directorate General of Maritime Affairs as the implementing unit. The matter is regulated by the “Directive on the Determination and Notification of the Gross Weights of Loaded Containers to Be Carried by Sea” (Denizyoluyla Taşınacak Dolu Konteynerlerin Brüt Ağırlıklarının Tespiti ve Bildirimi Hakkında Yönerge), which also entered into force on 1 July 2016. Method 2 approval, the authorisation of weighing facilities, and the scope of the declaration are defined in this text.

The weighing instrument itself is subject to separate regulation: it must be a non-automatic weighing instrument compliant with weights-and-measures rules, stamped, and with valid calibration.

The SOLAS text does not itself contain a deviation tolerance; the national authority sets the figure. In Türkiye the tolerance is defined in the Directive above and, since it can change, should be confirmed against the text currently in force. Tolerance is not “licence to round,” it is a margin for measurement uncertainty — it does not legitimise an estimated figure.

LCL, Ro-Ro and cases outside scope

For LCL shipments, the declaration is given by the consolidator, because it is the party named as shipper on the master bill of lading and is responsible for the container as a whole. The cargo owner’s job is to report the true weight and dimensions of its own consignment accurately to the consolidator. An error here does double damage: the consolidator’s VGM is thrown off, and the cargo owner’s chargeable weight comes out wrong, with the difference invoiced later.

The rule applies to loaded containers covered by the CSC, in sea transport. Empty containers are outside its scope. The exceptions are narrowly defined: containers carried on a chassis or trailer, driven on and off a ro-ro vessel, on ships making a short international voyage, and offshore containers designed to be handled in open water, are outside the rule’s scope. Cargo going by ro-ro does not, on its own, create an exemption; the conditions must be met together. If in doubt, get written confirmation from the carrier.

Common mistakes and a final check before declaring

• Mistaking net weight for VGM. The most common mistake. The net kilogram figure from the invoice is declared, and the tare and packaging are forgotten.
• Not counting pallets and securing material. The 450 kg of pallets and 60 kg of securing material in the worked example get lost exactly this way.
• Writing the tare from an estimate. The correct source is the TARE line in that specific container’s weight markings — not a type average. The CSC plate does not substitute for this line; it gives the maximum gross weight.
• Using Method 2 on unsuitable cargo. For scrap, mixed consolidated loads and cargo with undocumented weight, weighing is the only way.
• Mistaking the VGM cut-off for the documentation cut-off. These are two different times, and the VGM cut-off closes earlier on most carriers; confirm the applicable time from the booking confirmation.
• Leaving the declaration to the last minute. A weighbridge queue or a portal outage is not treated as an excuse once the time has passed.
• Assuming responsibility has been transferred to the forwarder. Whoever is named as shipper on the bill of lading is responsible for the accuracy of the declaration.

Before sending, check in order:

1. Do the container and booking numbers match the declaration
2. Was the tare read from that specific container’s own TARE line
3. Were pallets, packaging and securing material included in the total
4. Is the VGM below the maximum gross weight on the plate
5. If Method 1 was used, is the weighbridge ticket on file
6. Is the signatory authorised, and is the name written in capital letters

If you cannot show where a figure came from, do not send the declaration. For the channel and cut-off time, check your carrier’s booking confirmation; for tolerance and method approval, check the Directive currently in force.