ICAO registration marks (N-reg, M-reg, VP-C)
Every civil aircraft carries a registration prefix identifying its state of registry, such as N for the United States, G for the UK, D for Germany, M- for the Isle of Man, VP-C for the Cayman Islands, T7 for San Marino and 9H for Malta. The registry determines which authority certifies the aircraft and its crew, which tax and mortgage rules apply and whether the aircraft can be used commercially. N-registration is popular worldwide because of the depth of the US market and the fact that non-US owners can register through a trust. Offshore registries like Isle of Man and Cayman are used by private owners for neutrality and resale value; they generally do not allow charter, so aircraft moving onto an AOC must be re-registered.