Sir John Hall Magowan, KBE, CMG was a British diplomat. Raised in Mountnorris, Co. Armagh, he was educated at the Royal School, Armagh and Trinity College, Dublin. He married Winifred Isabel and had a daughter, Ann Isabel Magowan, and two sons, William Andrew Magowan and David Magowan.

He served as British Ambassador to Venezuela from 1948 to 1951,^[1] and died while back in Northern Ireland on leave on 5 April 1951.^[2] He had been appointed British Ambassador to Thailand in December 1950, but died before he could present his credentials.