"Scillonian III" has a length of 68 m, a beam of 11.85 m, a draft of 2.89 m, a gross tonnage of 1255.25, and a service speed of . Due to the number of tidal currents which meet off Land's End, and the need for a shallow draught to allow access to the Islands, the sea journey can be rough, causing sea sickness. For this reason the ship is fitted with a "Flume" antiroll stabiliser system. The ship is also designed to have a shallow draft and can sit on the seabed when there is insufficient water.