He married Claire Catlow OBE on 14 June 1969. The couple has three daughters and a son:
Hon. Alexandra Louise Macdonald, b. 19 Aug 1973, married the German-Austrian nobleman and landowner Philipp zu Guttenberg (b. 1973), brother of German politician Karl-Theodor zu Guttenberg
Hon. Isabella Claire Macdonald, b. 2 Oct 1975
Hon. Meriel Iona Macdonald, b. 1978
Hon. (Godfrey Evan) Hugo Thomas Macdonald, b. 24 Feb 1982.
Lady Macdonald is a noted cook and food writer.[2]
Lord Macdonald succeeded to the title Baron Macdonald in 1970 on the death of his father.
He was an elected member of Invernessshire County Council 1970–1975 and of Skye and Lochalsh District Council 1975–1983.