Egmont was the third but eldest surviving son of Charles Perceval, 2nd Baron Arden, eldest son of John Perceval, 2nd Earl of Egmont, by his second wife Catherine, Baroness Arden. Prime Minister Spencer Perceval was his uncle.

Egmont left Harrow school and was commissioned into the Royal Navy as a powder monkey in August 1805 and fought in HMS Orion in the Battle of Trafalgar the same year, aged eleven.^[1] During the Bombardment of Algiers in 1816 he commanded HMS Infernal. He was promoted to rear-admiral on 27 August 1851,^[2] to vice-admiral in 1857 and to admiral in 1863.

Egmont was returned to Parliament as one of two representatives for Surrey West in 1837, a seat he held until 1840. The latter year he succeeded his father in the barony of Arden and entered the House of Lords. The following year he also succeeded his half-first cousin once removed, Henry, as sixth Earl of Egmont.

The wills of the 4th and 5th Earls of Egmont were not proven until 1857, after the death of the family solicitor Sir Edward Tierney, by Tierney's son-in-law Sir William Darell. The 6th Earl contested the 5th Earl's will in 1863, on the grounds that Tierney had taken advantage of the 5th Earl's drunkenness to provide a misleading valuation of the estates which influenced the drafting of the will. The 6th Earl ultimately settled out of court with Darell, paying £125,000 for the return of the family estates in Churchtown, County Cork; Tierney and his heirs had realized an estimated £300,000 for their stewardship.^[3]

Lord Egmont married Jane, daughter of John Hornby, in 1819. They had no children. Lady Egmont died in October 1870. He survived his wife by four years and died in August 1874, aged 80. He was succeeded in the earldom by his nephew, Charles.

His probate was sworn the same year at under a rounded threshold of £350,000 (equivalent to about £34,600,000 in 2021), the public calendar of which states he died at Nork House, Banstead, which was one of his addresses, the others being 26 St James's Place, St James's and the mansion of Cowdray Park, West Sussex which takes in Cowdray House (extensive and in part very tall, crenular medieval, Tudor and Stuart ruins).^[4]

• O'Byrne, William Richard (1849). "Perceval, George James" . A Naval Biographical Dictionary . John Murray – via Wikisource.

• Leigh Rayment's Peerage Pages ^{[self-published source] [better source needed]}
• Leigh Rayment's Historical List of MPs
• New York Times obituary

• Hansard 1803–2005: contributions in Parliament by the Earl of Egmont