vyv_cox
Well-known member
If you are going outside of UK waters the MMSI is the one that is more readily understood and accessible to marine authorities and can be used by anyone with a dsc vhf to call you. Otherwise, mobile number (with country code if going abroad)
Www.solocoastalsailing.co.uk
Having kept my boat outside UK since 1996 I have never found the 'marine authorities' to have the slightest interested in my MMSI number. I have never needed to tell or relay it to anyone and without looking it up I have no idea what it might be. I last used it to enter it into a new VHF and the time before that was for the same purpose.