Notices to mariners

What are Notices to Mariners?


Changes at sea happen continously. The Hydrographic Office monitors these changes and then publishes the corrections to it’s publications – it issues a Notice to Mariners. Notices to Mariners are corrections to charts and publications that are vital to safety at sea. The NtM gives mariners up-to-date information about the current situation as sea. It is important for all mariners to keep the latest editions of charts and publications.


The South African Navy issues a Notice to Mariners publication. This is a compilation of all South African chart and publication updates issued every month. The NtM has six sections:

  • Explanatory Notes and Index
  • SAN Notices to Mariners. Updates to Standard Navigational Charts
  • South African Charts and HO Publications – New Charts/Editions
  • Corrections to SAN HO Publications
  • Corrections to SA List of Lights and Radio Services
  • Reprints of Radio Navigational Warnings


The British Admiralty also issue Notices to Mariners.

Helpful Links

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