IOM Class Rules

The International One Metre (IOM) Class Rules set out the specifications that a boat must comply with to be certified as an IOM.  The Class Rules are to be read in conjunction with World Sailing’s Equipment Rules of Sailing (ERS) which provide several key definitions. The IOM Class Rules are updated when Special Resolutions are passed by the IOM ICA World Council in accordance with the IOM ICA Constitution.  The current version of the IOM Class Rules is valid from March 2026 and reflect resolutions passed at the 2025 World Council meeting.