Notices to mariners

Notices to Mariners (NtM) are published by a range of organisations to provide essential navigational updates. They typically include: 

• Navigation chart updates 

• Changes in buoyage and other aids to navigation 

• Warnings about works, surveys, or operational activities that may affect safe passage 

Where to find Notices to Mariners

Port and harbour authorities

Many port and harbour authorities publish local area NtM on their websites. Most also offer email alerts that mariners can subscribe to.

ADMIRALTY chart updates and radio navigation warnings

The ADMIRALTY Small Craft Chart Service (a service of the UK Hydrographic Office) issues NtM to keep Small Craft Charts up to date. It also publishes Radio Navigation Warnings, including NAVAREA I and UK coastal warnings. These can be found on the ADMIRALTY website.

Imray

Imray provides an online chart correction service, whereuserscansearch for updates by chart number.

General Lighthouse Authorities

The General Lighthouse Authorities publish NtM for waters outside the jurisdiction of port and harbour authorities.

Trinity House

Trinity House is the general lighthouse authority for England, Wales, the Channel Islands and Gibraltar. Its website provides NtM, including notices of works and events that may affect navigation.

Northern Lighthouse Board(NLB)

The Northern Lighthouse Board is responsible for Scotland and the Isle of Man. It manages more than 200 lighthouses and nearly 200 buoys, and publishes NtM covering its operational area.

Commissioners of Irish Lights

Irish Lights provides aids to navigation around the Irish coastline. Its NtM include updates to navigational aids and details of works and events with potential impacts on mariners.