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Marine radio

What does an MMSI identify?

Short answer

An assigned maritime radio station or group identity

The nine-digit MMSI identifies a maritime station or assigned group call over the radio path. It is separate from channel selection.

Sources and scope

Reviewed by Richard Moore on . This answer is scoped to united kingdom marine vhf and internationally harmonised procedure; check the current chart, publication, local rules and official operational guidance before acting afloat.

Quick check

What does an MMSI identify?