MMSI Maritime Mobile Service Identity

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.

When used

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.
  • Coast Guard ground stations.

Which devices use MMSI:

  • The AIS transponder
  • The VHF with DSC functionality (enabled only if the master holds one of the following certificates: GOC, ROC, LRC or SRC).
  • An MF/HF transmitter equipped with DSC (normally found on vessels subject to GMDSS).

From whom you are released

The MMSI code is assigned by the competent authority of your country, which in Italy is recognized in the Regional Inspectorate of the Ministry of Economic Development - Communications.

The MMSI code can be issued for all types of vessels, including vessels.