Grain Shipping

What is grain as a sea-borne cargo?

Grain is the collective name for cereal seed cargoes carried in bulk by sea. It covers wheat, corn (maize), soybeans, barley, sorghum, oats, and rye, plus pulses and oilseeds traded under grain-style charter parties. The IMO treats grain as a special bulk cargo with its own stability code.

In commercial practice, “grain” on a fixture note usually means one nominated commodity, loaded clean into clean holds, carried to a single discharge port, and surveyed at both ends. The cargo is free-flowing, low to medium density, and almost always carried in geared or gearless Panamax, Supramax, and Handysize tonnage. Capesize grain stems exist but are unusual outside soybean and corn parcels from Brazil and the US Gulf.

Two regulatory regimes apply at the same time. The IMSBC Code 2024 GRAIN schedule covers cargo description, hazards, and routine carriage. Separately, the IMO International Grain Code, made mandatory under SOLAS Chapter VI Part C, governs the intact stability of any vessel loading bulk grain. The master must hold an approved grain loading booklet and submit a stability calculation before loading begins. This is the operational gate that separates grain from every other Group C dry bulk cargo.

Grain cargo properties

Property	Value	Unit / Reference
Stowage factor (wheat)	1.35 to 1.45	m3/t
Stowage factor (corn)	1.30 to 1.40	m3/t
Stowage factor (soybeans)	1.30 to 1.40	m3/t
Stowage factor (barley)	1.45 to 1.55	m3/t
Bulk density	0.70 to 0.80	t/m3
Angle of repose	25 to 35	degrees
IMSBC group	C	Not liable to liquefy, not chemically hazardous
IMSBC schedule entry	GRAIN	IMSBC Code 2024
Stability regime	IMO International Grain Code	SOLAS Chapter VI Part C
Transportable moisture limit	Not applicable	Group C cargo
Hazard class	Not applicable	Subject to fumigation controls
Typical fumigant	Phosphine (PH3)	Aluminium or magnesium phosphide pellets

Stowage factors vary with moisture, variety, and the bushel weight declared by the shipper. Tighter packing of soybeans against the looser stow of barley means the same hold cube can carry materially different deadweight depending on the parcel.

Vessel typing and parcel sizes

Hold cleanliness is the dominant operational gate. Grain receivers require holds to pass a food-grade survey before loading, with no rust scale, no prior cargo residue, no loose paint, and dry bilges. A fail at the load port sends the vessel back to sea to re-clean, and laytime exposure follows the charter party. See Panamax bulk carriers for the dominant grain class and Supramax and Handysize for the geared options.

How grain ships in practice

Hold preparation starts before the vessel arrives. Crew sweep, wash, and dry holds, then present them to a third-party surveyor nominated by the receivers or by FOSFA where the charter party calls for it. The survey is the operational pass-fail. Failed holds delay the notice of readiness and trigger laytime arguments under the voyage charter terms.

Loading proceeds in stages tied to the grain code stability calc. The master receives a shipper’s certificate that declares cargo type, moisture, test weight, and (where required) the loadable bushel density. Stowage is planned so that the partly filled holds, the heeling moments, and the free surface effect all comply with the approved booklet. The grain code certificate is issued before the vessel sails.

Fumigation usually happens at the load port or in transit. Aluminium phosphide tablets are placed in the cargo, releasing phosphine gas over five to ten days. The IMSBC Code requires gas-tight hold sealing, a fumigant-in-transit notification on the cargo documents, and ventilation procedures before discharge. The disconnect between the fumigation cycle and the discharge schedule is a frequent source of dispute, especially on short Black Sea to North Africa voyages where exposure time is tight.

At discharge, holds are ventilated, gas-tested, and opened. Shore grabs or pneumatic suckers work the cargo. Final survey at discharge cross-checks moisture, foreign matter, and any sign of damp damage. Shortage and quality claims are settled against the load-port shipper’s certificate and the discharge survey. See demurrage and laytime for the time-counting mechanics that govern most grain fixtures.

Major trade routes

The grain trade is dominated by a small number of structural lanes. Volumes shift seasonally with northern and southern hemisphere harvests, so a given lane can be busy for six months and quiet for the other six.

• US Gulf to East Asia. Corn and soybeans on Panamax and the occasional Capesize. Mississippi River loadings via New Orleans, with Asian receivers in China, Japan, South Korea, Taiwan, and Vietnam.
• US Pacific Northwest to East Asia. Wheat, corn, soybeans on Panamax. Direct Pacific routing from Columbia River, Vancouver USA, Tacoma, and Portland. Shorter voyage than the Gulf alternative for many Asian receivers.
• Brazil to China. Soybeans on Panamax and Capesize. Santos, Paranagua, and northern arc ports (Itaqui, Barcarena). Southern hemisphere harvest peaks the lane from February to August.
• Argentina to Asia and North Africa. Soybeans, soyameal, wheat, corn on Panamax. Up-river Parana ports (Rosario, San Lorenzo) with draft restrictions that constrain top-off operations.
• Australia to the Middle East and Asia. Wheat on Panamax and Supramax. Esperance, Kwinana, Geelong, and Newcastle. Counter-seasonal to the northern hemisphere harvest.
• Black Sea to North Africa and the Middle East. Wheat and corn on Supramax and Handysize, with Panamax on the larger receivers. Russian, Ukrainian, and Romanian loadings into Egypt, Algeria, Tunisia, and Saudi Arabia.
• EU to North Africa. Wheat on Handysize and Supramax. French Atlantic ports and Hamburg, into Algeria and Morocco.

Grain vs fertilizer

Grain and bulk fertilizer share the Panamax and Supramax fleet, both move as free-flowing Group C cargo on most schedules, and both are sensitive to moisture ingress. The differences sit in the regulatory regime and the receiver chain.

Select grain when the cargo is for human food, feed, or oilseed crush, and accept the grain code paperwork and the food-grade survey as the cost of entry. Select fertilizer carriage when the receiver is agricultural and the operational focus shifts from food safety to hygroscopic control and, for AN-based grades, self-decomposition risk. See fertilizer shipping for the parallel page.

Reference example

01 Fixture Example

Panamax Wheat, Black Sea to North Africa

Cargo

Milling wheat, bagged loadability not required

Lane

Western Black Sea to North Africa

Vessel band

Panamax, 75,000 dwt class

Parcel size

60,000 t, 10 percent more or less in owners option

Load rate

12,000 t per weather working day

Discharge rate

5,000 t per weather working day, two berths

Laytime

Reversible, see voyage charter party

Charter party form

GRAINCON 2003 amended

Notable clause

Grain code certificate to be on board prior to NOR. Holds passed by independent surveyor before loading. In-transit phosphine fumigation, ventilation prior to opening at discharge.

The fixture above is anonymised. It illustrates the standard structure of a single-commodity grain voyage on a regional lane, with the grain code certificate and the hold pass survey as the two operational gates that anchor the fixture.

Image Placeholder Panamax bulk carrier loading milling wheat at a Black Sea grain terminal Stylised image: Panamax at a grain berth, two shore loaders, conveyor gantry, calm water, late afternoon light.

Common loading and discharge issues

• Damp hold at discharge leading to receiver rejection of a parcel or part of a parcel, with moisture migration traced to either condensation in transit or trace water from incomplete drying after wash-down at the load port.
• Fumigation timing disputes. Short voyages do not allow the full phosphine exposure cycle, and receivers reject cargo where the certified treatment time is not met.
• Grain code stability calc dispute. The shipper-declared bushel weight does not match the surveyed loaded weight, and the master must re-run the booklet calculation, sometimes shifting cargo between holds.
• Foreign matter and admixture above contract tolerance. Discharge survey finds dust, insects, or non-grain material above the FOSFA or contract-specified limit.
• Heat damage in tropical transit, especially on soybean and corn parcels where high moisture at loading allows self-heating during the voyage.
• Documentation gaps. Missing or late grain code certificate, missing fumigation-in-transit notification, or contradictory shipper certificates that delay clearance at the discharge port.

Scope and what this page does not cover

This page is an operational and cargo-spec briefing on bulk grain. It does not forecast wheat, corn, or soybean prices, it does not publish freight indices, and it does not offer broker-desk opinion on individual fixtures. Jurisdiction-specific case law on grain claims, especially under FOSFA, GAFTA, and English law arbitration, is outside the scope of this page and should be referred to qualified maritime counsel. For commercial pricing and current fixture flow, contact the dry cargo desk directly.