It is essential to book all ferries in advance.
There are two commercial ferry routes to the Isle of Barra, operated by Caledonian MacBrayne. From Oban, on the mainland, the Castlebay sailing takes just under five hours. If you are already on the Outer Hebrides, catch the ferry from the island of Eriskay to Ardmhor on Barra. This sailing takes about 45 minutes.
Visit CalMac for more details.