Born on 7 Sep 1839 at Clapham, third son of Thomas Alers Hankey of Clapham and Educated at Harrow and Trinity College, Cambridge.
He was married on 7 Sep 1865 at Riddlesworth to Louisa Fanny (1844-1921), daughter of Thomas Thornhill of Riddlesworth Hall, Norfolk, by whom he had two sons and four daughters.
By 1869 the family home was Lock’s Farm, Wokingham and later Heathlands House, Wokingham (where in 1881 there were 13 domestic staff. Also there were all his children except Sydney, who was among the 37 boys at Sunningdale School). Sydney was JP and DL for Berkshire; High Sheriff 1885.
He died on 2 Jan 1920, aged 80, leaving effects of £56,118. He was then living at Breck, Knyveton Road, Bournemouth.
Sydney took a great interest in Hankey family history, and regularly corresponded with his cousin Henry Alers Hankey on the subject.