 Assuming that Domhnall is not the "dead man at Ballyshannon", the date of Domhnall's death cannot be fixed. MacDonald tradition placed it in 1289, a tradition usually rejected by modern historians as falling far too late. R. Andrew McDonald suggested that Domhnall's death must have taken place before 1263, when King Haakon collected the allegiance of Aonghus Mór in the Hebrides. Alex Woolf argued that it very likely must have occurred before February 1256, when Domhnall's son Aonghus Mór made a grant to Paisley Abbey is his own name as "Lord of Islay", suggesting at the very least that Domhnall had retired.
