The MMSI (Maritime Mobile Service Identity) is a 9-digit number and uniquely identifies the vessel in on-board radio transmissions.
How it is structured
The MMSI code consists of 9 digits, which for reasons of legibility is normally separated into 3 groups of 3 digits. The first 3 digits make up the MID (Maritime Identification Digit) and identify the nationality, which in the case of Italy is 247. The remaining 6 digits are assigned by the competent authority.
In the case of coastal stations, the MID is moved after the first 2 digits, for example the MMSI of the Roma Radio station is 002470001.
Who must be in possession of the MMSI:
It is mandatory when the ship is subject to the GMDSS system.
When the boat uses devices that need to digitally transmit this identifier.