Shipper-Owned Containers: A Practical UK Guide to SOC Shipping

What Is the Difference Between an SOC and a COC?

A carrier-owned container, or COC, comes from the shipping line’s equipment fleet. It normally has to be collected, loaded, discharged, emptied and returned within the carrier’s agreed free time.

With an SOC, the cargo interest controls the container and remains responsible for its condition after discharge. This can remove exposure to charges for retaining the carrier’s equipment, but it does not automatically remove port storage, terminal handling, haulage waiting time or SOC booking charges.

When Does an SOC Make Commercial Sense?

Shipper-owned containers are particularly useful when controlling the equipment is more important than quickly returning it to a shipping line.

• Project cargo: Machinery, construction materials and engineering equipment may be assembled or packed over an extended period.
• Remote destinations: The consignee may need to retain the container because suitable warehousing or empty-container depots are unavailable.
• Destination storage: Once unloaded, the unit can remain on-site for secure storage rather than being returned immediately.
• Recurring traffic: Businesses operating regular routes may prefer to control their own equipment availability and maintenance.
• Special cargo: A business may require a particular configuration, such as a refrigerated container, flat rack, open-top unit or specially prepared dry container.

The calculation should include more than the purchase price. Allow for inspection, repairs, repositioning, storage of empty equipment, inland haulage, insurance, carrier acceptance fees and customs treatment. An SOC avoids retaining someone else’s container, but it remains an asset that must be managed.

SOC Compliance: Three Checks That Cannot Be Ignored

1. CSC Safety Approval Plate and Examinations

The International Convention for Safe Containers 1972 establishes safety approval, testing, examination and maintenance requirements for most freight containers used in international surface transport.

The International Maritime Organisation’s CSC guidance states that an approved container bears a Safety Approval Plate with relevant technical data. Approval granted by one contracting state should be recognised by other contracting states.

Crucially, the IMO states that subsequent maintenance of a safety-approved container is the owner’s responsibility. Ownership of an SOC, therefore, brings a continuing obligation to keep the unit safe and to arrange the required examinations.

For containers operated from Great Britain, the Health and Safety Executive’s freight-container guidance says containers must be:

• approved for their design and construction;
• regularly examined by a competent person;
• maintained in efficient working order and good repair;
• fitted with a permanently affixed Safety Approval Plate; and
• marked so that the maximum operating gross mass agrees with the plate.

The HSE recognises two examination systems:

• Periodic Examination Scheme: the first examination must take place no later than 5 years after manufacture, followed by examinations at intervals of no more than 30 months.
• Approved Continuous Examination Programme: examinations are linked to events such as major repairs, refurbishment or on-hire and off-hire interchanges, but the interval must still not exceed 30 months.

A CSC plate should be legible, securely attached and supported by valid examination information. Check that the container number and maximum operating gross mass are consistent with the container’s other markings.

A plate is not a substitute for examining the actual container. Before packing, inspect the corner posts, corner castings, understructure, cross-members, roof, side panels, doors, locking gear and floor. Severe corrosion, cracking, distortion of structural members, or unsuitable modifications require assessment by a competent specialist.

2. Verified Gross Mass

Verified Gross Mass, or VGM, is the verified combined mass of the packed cargo, packaging, securing materials and the container itself.

The IMO’s VGM guidance and the UK Maritime and Coastguard Agency’s official container-weight guidance place responsibility for providing the VGM on the shipper.

The VGM must be stated in the shipping document, signed by a person authorised by the shipper and supplied to the master or the master’s representative and the terminal sufficiently early for preparation of the vessel’s stowage plan.

Without a VGM, a packed container must not be loaded onto the ship. This applies whether the equipment is an SOC or a carrier-owned container.

The MCA publishes an enforcement tolerance of plus or minus 5% or 500kg, whichever is greater. Its guidance makes clear that this is for enforcement purposes only. It is not an allowance that permits shippers to estimate or deliberately round a container’s weight.

3. Customs Treatment of the Cargo and Container

Owning the container does not remove customs formalities for the goods inside it. Cargo and container equipment may need to be considered separately.

For permanent commercial imports into England, Scotland or Wales, GOV.UK states that a business generally needs a GB EORI number. The correct commodity code must be entered on the import declaration because it affects duty rates, licensing and other controls.

HMRC lists containers and qualifying reusable packaging among the goods that may be eligible for Temporary Admission when imported temporarily for re-export, subject to the relevant conditions. Depending on the movement and location, an oral declaration or declaration by conduct may sometimes be available.

Do not assume that a simplified declaration is accepted at every port. HMRC specifically states that oral Temporary Admission declarations cannot be accepted at Roll-on/Roll-off locations such as Dover and Eurotunnel. Check the intended border location and procedure with your customs agent before the unit moves.

For EU imports into Great Britain, Entry Summary Declarations have been required since 31 January 2025. GOV.UK states that the carrier or haulier is legally responsible for making the declaration, although an importer or intermediary may lodge it on the carrier’s behalf.

The British International Freight Association’s Safety and Security guidance provides useful operational information for freight forwarders. BIFA guidance should be read alongside current HMRC, MCA and IMO requirements rather than used as a substitute for them.

SOC Shipping Checklist

1. Confirm the route: identify the loading point, ports, transhipment locations, final destination and intended use after discharge.
2. Obtain carrier acceptance: tell the carrier or forwarder at quotation stage that the booking will use an SOC.
3. Verify ownership: retain the invoice, lease agreement or other evidence showing the right to use the container.
4. Check its identity: ensure container markings are clear, consistent and acceptable to the carrier and terminals.
5. Validate CSC status: inspect the Safety Approval Plate, next examination date or ACEP details and supporting records.
6. Inspect its condition: confirm that the structure, doors, seals, flooring and securing points are fit for the cargo and journey.
7. Plan the load: stay within the CSC maximum operating gross mass, road limits and the equipment’s structural ratings.
8. Establish the VGM using Method 1 or an approved Method 2 process, and submit the signed information before the carrier’s cut-off.
9. Complete customs formalities: deal with the cargo declaration and the customs status of the reusable container as separate questions.
10. Insure the risks: check cargo, equipment, third-party liability and storage cover, including what happens after discharge.

Choosing an SOC in Manchester

The right unit depends on the cargo, gross mass, route, loading method and what will happen to the container at destination. A standard 20ft container is often selected for dense or heavy cargo, while a 40ft container provides more internal capacity for bulky loads.

Browse our wider container range and tell us whether the unit is intended for on-site storage, modification, or an international shipment. Requirements for a shipping SOC are different from those for a container that will remain permanently at a Manchester site.

Shipping Containers of Manchester supplies businesses and individuals across Greater Manchester. Container condition, proposed modifications, delivery access and your intended route should all be discussed before purchase.