What Is Maritime Law?

Maritime law, also known as admiralty law, is a body of laws, conventions, and treaties that govern private maritime business and other nautical matters, such as shipping or offenses occurring on open water. International rules, governing the use of the oceans and seas, are known as the Law of the Sea.

Understanding Maritime Law

In most developed nations, maritime law follows a separate code and is an independent jurisdiction from national laws. The United Nations (UN), through the International Maritime Organization (IMO), has issued numerous conventions that can be enforced by the navies and coast guards of countries that have signed the treaty outlining these rules. Maritime law governs many of the insurance claims relating to ships and cargo; civil matters between shipowners, seamen, and passengers; and piracy.

Conventions are regularly amended to keep up with new business practices and technologies


Additionally, maritime law regulates registration, license, and inspection procedures for ships and shipping contracts; maritime insurance; and the carriage of goods and passengers.

The IMO (established in 1948 as the Inter-Governmental Maritime Consultative Organization, and coming into force in 1958) is responsible for ensuring that existing international maritime conventions are kept up to date, as well as developing new agreements as and when the need arises. 

Today, there are dozens of conventions regulating all aspects of maritime commerce and transport. The IMO names three conventions as its core:

  • The International Convention for the Safety of Life at Sea
  • The International Convention for the Prevention of Pollution from Ships
  • The International Convention on Standards of Training, Certification, and Watchkeeping for Seafarers

On its website, the IMO has a complete list of existing conventions, their historical amendments, and explanatory notes.

Key Takeaways

  • Maritime law governs private maritime questions, disputes, or offenses and other nautical matters.
  • In most developed countries, the maritime law follows a separate code and is an independent jurisdiction from national laws.
  • The IMO ensures that existing international maritime conventions are kept up to date and develops new agreements when the need arises.

The governments of the of the 174 IMO member states are responsible for the implementation of IMO conventions for ships registered in their nation. Local governments enforce the provisions of IMO conventions as far as their ships are concerned and set the penalties for infringements. In some cases, ships must carry certificates onboard to show that they have been inspected and have met the required standards.

Special Considerations

The country of registration determines a ship's nationality. For most ships, the national registry is the country where the owners live and operate their business.

Ship owners will often register their ships in countries that allow foreign registration. Called "flags of convenience," the foreign registration is useful for tax planning and to take advantage of lenient local laws. Two examples of "flags of convenience" countries are Panama and Bermuda.