Sefton was returned to Parliament for Lancashire South in 1832, a seat he held until 1835.

[1] In 1838 he succeeded his father in the earldom and took his seat in the House of Lords.

Lord Sefton married Mary Augusta, daughter of Robert Gregg-Hopwood, in 1834.

He died in August 1855, aged 59, and was succeeded by his eldest son, William.

The family seats were: Croxteth Hall, Lancashire ; Stoke Farm, now called Sefton Park in Stoke Poges, Buckinghamshire;[2] and Sefton House (later known as Seaford House) in Belgrave Square, London.