Ship Radio Versus Ship Portable

The Ship Radio Licence authorises equipment on the named UK-flagged vessel wherever that vessel sails, subject to the licence and local requirements. Declared handhelds may be used under that vessel's licence, but a DSC handheld carrying the ship MMSI must not be casually moved to another boat.

A Ship Portable Radio Licence is not tied to one named vessel. It can authorise specified portable equipment used aboard different vessels, but its UK licence authority stops at the limit of UK, Channel Islands or Isle of Man territorial seas. The equipment is used aboard a vessel or tender, except that emergency use may occur anywhere.

Portable identities differ from ship identities. A portable licence can carry a T reference and an MMSI assigned for the handheld equipment; it does not assign a ship call sign. A portable MMSI identifies the apparatus and licensing arrangement, not whichever vessel it happens to be aboard.