Vacsay is a small island in Loch Roag a few hundred metres off Reef Beach (Tràigh na Beirigh). It was once inhabited but is now used only for grazing. Ruined buildings are shown in the bay on the south side of the island (opposite the islet of Tràthasam) on the Ordnance Survey map of 1854.

(Note that there is a smaller island also called Vacsay just off Kirkibost on Great Bernera.)