His mother was Arabella Charlotte, daughter of T. S. D. Bucknell.
He was educated at Eton and Christ Church, Oxford.
[2] Hanmer sat as Member of Parliament for Shrewsbury between 1832 and 1837, for Kingston upon Hull between 1841 and 1847 and for Flint Boroughs between 1847 and 1872.
Lord Hanmer died in March 1881, aged 71, and was buried at Bettisfield, Flintshire.
The barony became extinct on his death while he was succeeded in the baronetcy by his younger brother, Wyndham.