Register and operate a sea-going ship

Operating ships commercially from the UK means registering the vessel, keeping it surveyed and certified, and running it under international safety, security and environmental regimes. These requirements apply to sea-going passenger and cargo ships on coastal and international voyages. The Maritime and Coastguard Agency (MCA) administers UK maritime regulation and the UK Ship Register; these regimes apply across the United Kingdom under the Merchant Shipping Act 1995.

Register the ship (UK Ship Register)

A commercially operated ship must be registered on the UK Ship Register, operated by the MCA, to fly the UK flag and obtain certificates. Part I registration covers larger merchant ships and allows a mortgage to be registered; the Small Ships Register covers vessels under 24 metres. You can also transfer registration between British maritime jurisdictions in the Red Ensign Group without losing your Official Number.

Survey and safety certification

Ships must be surveyed by the MCA or a recognised organisation and hold valid safety certificates before operating — passenger ships hold a Passenger Ship Safety Certificate and the SOLAS construction, equipment and radio certificates; cargo ships hold the equivalent cargo-ship certificates. Surveys are periodic — typically annual, intermediate and renewal. Passenger ships carry additional duties on passenger counting, evacuation, life-saving appliances and damage stability.

Load line

Ships of 24 metres or more must be surveyed and marked with a load line and hold an International Load Line Certificate certifying minimum freeboard and reserve buoyancy for the trade and cargo carried.

ISM Code safety management

Passenger ships on international voyages, and cargo ships of 500 gross tonnage and over on international voyages, must operate a Safety Management System under the International Safety Management (ISM) Code and hold a Document of Compliance (company) and a Safety Management Certificate (ship), issued and audited by the MCA. Small domestic passenger ships use the Domestic Safety Management Code instead.

Carriage of dangerous goods (IMDG Code)

If you carry dangerous or harmful cargo, packaged and bulk dangerous goods must be classified, packed, marked, documented and stowed in accordance with the IMDG Code (SOLAS Chapter VII / MARPOL Annex III). This applies only where the operator carries dangerous or harmful cargo.

Maritime security (ISPS Code)

Ships and the port facilities they use on international voyages must meet the International Ship and Port Facility Security (ISPS) Code — a ship security assessment and plan, a Ship Security Officer, and an International Ship Security Certificate. The Aviation and Maritime Security Act 1990 underpins UK implementation.

Environmental compliance (MARPOL)

Ships must meet the MARPOL pollution-prevention regimes — including the sulphur limits on marine fuel and, for larger ships, ballast water management to control the transfer of invasive species.

Reporting marine accidents (MAIB)

Accidents, serious injuries and dangerous occurrences involving the ship must be reported to the Marine Accident Investigation Branch (MAIB), made under section 267 of the Merchant Shipping Act 1995 and the Merchant Shipping (Accident Reporting and Investigation) Regulations 2026, which replaced the 2012 Regulations on 15 May 2026.

Tonnage Tax

Tonnage Tax is an alternative way to calculate Corporation Tax for qualifying shipping companies — tax based on the deemed profit by tonnage rather than commercial profit. It requires a ten-year commitment and that strategic and commercial management is in the UK, so it is not suitable for every business model.