He left for London in 1825, intending to practise law in the capital but had difficulty making his way, and began contributing to the Sporting Magazine. He launched out on his own with the New Sporting Magazine in 1831, contributing the comic papers which appeared as Jorrocks' Jaunts and Jollities in 1838. Jorrocks, the sporting cockney grocer, with his vulgarity and good-natured artfulness, was a great success with the public, and Surtees produced more Jorrocks novels in the same vein, notably Handley Cross and Hillingdon Hall, where the description of the house is very reminiscent of Hamsterley. Another hero, Soapey Sponge, appears in Mr Sponge's Sporting Tour, possibly Surtees best work. All Surtees' novels were composed at Hamsterley Hall, where he wrote standing up at a desk, like Victor Hugo.
In 1835, Surtees abandoned his legal practice and after inheriting Hamsterley Hall in 1838, devoted himself to hunting and shooting, meanwhile writing anonymously for his own pleasure. He was a friend and admirer of the great hunting man Ralph Lambton, who had his headquarters at Sedgefield County Durham, the 'Melton of the North'. Surtees became Lord High Sheriff of Durham in 1856. He died in Brighton in 1864 and was buried in Ebchester church.
Though Surtees did not set his novels in any readily identifiable locality, he uses North East place-names like Sheepwash, Howell (How) Burn, and Winford Rig. His memorable Geordie, James Pigg in Handley Cross is based on Joe Kirk, a Slaley huntsman. The famous incident, illustrated by Leech, when Pigg jumps into the melon frame was inspired by a similar episode involving Joe Kirk in Corbridge. As a creator of comic personalities, Surtees is still very readable today. Thackeray envied him his powers of observation, while William Morris considered him 'a master of life' and ranked him with Dickens. The novels are engaging and vigorous, and abound with sharp social observation, with a keener eye than Dickens for the natural world. Perhaps Surtees most resembles the Dickens of Pickwick Papers, which was originally intended as mere supporting matter for a series of sporting illustrations to rival Jorrocks.
Most of Surtees's later novels, were illustrated by John Leech. They included Mr Sponge's Sporting Tour (1853); Ask Mamma (1858); Plain or Ringlets? (1860)and Mr Facey Romford's Hounds (1865). The last of these novels appeared posthumously.
In 1841 Surtees married Elizabeth Jane Fenwick, daughter of Addison Fenwick of Bishopwearmouth, by whom he had one son and two daughters. His younger daughter Eleanor married John Vereker, afterwards 5th Viscount Gort. Their son was Field Marshal Lord Gort, commander of the BEF in France in 1940.