Armstrong made numerous and generous financial donations to charitable institutions in and around Newcastle, including the Northern Counties Institution for the Deaf and Dumb, the Hospital for Sick Children, The Royal Victoria Infirmary and the Prudhoe Memorial Convalescent Home. This subscription list for the Prudhoe Convalescent Home records a donation of £2000 made by Armstrong. In today's money, this would amount to in the region of £100,000.