One of a group of small lochs and lochans located on the steeply-sloping southern shore of Loch Ness in the Inverness district of Highland Council Area, Dearg Lochain lies at an altitude of 205m (672 feet) a quarter-mile (0.4 km) north northeast of Lochan Scristan and 2 miles (3 km) southwest of Foyers. It drains into Loch Ness via the short Allt a' Mhinn.