Local notice to mariners

A local notice to mariners is an authoritative instruction issued by a designated official, typically the harbormaster.

Other marine information such as new charts, channel depths, naval operations, and regattas is included.

The local notice to mariners may be obtained free of charge by contacting the appropriate Coast Guard district commander.

The text of the US material originated from section 422 of The American Practical Navigator, a document produced by the government of the United States of America.

Each issuing authority has its own series of LNTMs – there is no international standard numbering or indexing scheme.