1814 in the United Kingdom
- Monarch – George III
- Regent – George, Prince Regent
- Prime Minister – Robert Jenkinson, 2nd Earl of Liverpool (Tory)
- Parliament – 5th
- 14 January
- Treaty of Kiel cedes Danish Heligoland to Britain.
- Troopship Queen, newly returned from Spain, is driven ashore and wrecked on Trefusis Point near Mylor, Cornwall with the probable loss of at least 300.
- The third-coldest month in the CET series with an average of −2.9 °C or 26.8 °F allows the last River Thames frost fair in London.
- 26 January – actor Edmund Kean makes his London début in an adult leading rôle as Shylock at the Theatre Royal, Drury Lane.
- 12 February – a fire destroys the Custom House, London.
- 21 February – Great Stock Exchange Fraud in London.
- 1 April – the Gas Light and Coke Company begins the world's first permanent public gas lighting of streets in the parish of St Margaret's, Westminster, extending to other parts of London by 25 December.
- 10 April – the Duke of Wellington wins the Battle of Toulouse, ending the Peninsular War.
- 28 April – first running of the 1,000 Guineas Stakes horse race at Newmarket, won by Charlotte.
- 5 May – War of 1812: The British attack Fort Ontario at Oswego, New York.
- 30 May – Treaty of Paris: Britain takes control of Malta, Tobago, Saint Lucia, and Mauritius from France.
- 5 July – War of 1812: Battle of Chippewa – American Major General Jacob Brown defeats British General Phineas Riall at Chippewa, Ontario.
- 25 July
- War of 1812: Battle of Lundy's Lane – Reinforcements arrive near Niagara Falls, Ontario, for General Riall's British and Canadian force, and a bloody, all-night battle with Jacob Brown's Americans commences at 18.00; Americans retreat to Fort Erie.
- George Stephenson puts his first steam locomotive into service, the Blücher for Killingworth Colliery on Tyneside.
- 26 July – opening of Ryde Pier on the Isle of Wight, the first pier in Britain.
- 28 July to 13 September – poet Percy Bysshe Shelley abandons his pregnant wife and runs away with the sixteen-year-old Mary Wollstonecraft Godwin, accompanied by her stepsister Jane Clairmont (also 16), to France and Switzerland.
- 12 August – the last hanging under the Black Act in England is of William Potter for cutting down an orchard; the judge petitions for reprieve.
- 13 August – the Anglo-Dutch Treaty of 1814 is signed in London, returning most possessions of the Dutch Empire acquired by the United Kingdom since 1803 to the Netherlands, although Britain retains the Cape of Good Hope and the South American settlements of Demerara, Essequibo and Berbice (later consolidated as British Guiana). In addition, Britain cedes the island of Banca off the island of Sumatra in exchange for the settlement of Cochin in India.
- 24 August – War of 1812: The Burning of Washington: British troops burn Washington, D.C..
- 28 August – Alexandria, Virginia, offers surrender to the British fleet without a fight.
- 10 September – the last recorded duel in Wales is fought at Newcastle Emlyn: Thomas Heslop of Jamaica is killed; a local landowner, Beynon, is found guilty and fined one shilling.
- 17 October – London Beer Flood: a large vat of porter in Meux's Brewery bursts, demolishing buildings and killing nine.
- 23 October – the first plastic surgery carried out in England by Dr Joseph Constantine Carpue.
- 24 December – Treaty of Ghent signed by the United Kingdom and the United States ending the War of 1812, however due to the time it takes for news to reach America, fighting continues for weeks.
- Napoleonic Wars, 1803–1815
- Jeremiah Colman begins making Colman's mustard at Stoke Holy Cross mill near Norwich.
- James Purdey establishes his gunmaking business in London.
- John Abernethy appointed lecturer in anatomy to the Royal College of Surgeons.
- John Keats leaves apprenticeship to become a student at a local hospital.
- Britain's first public art gallery, the Dulwich Picture Gallery, opens.
- The Benedictine monastic community is established at Downside in Somerset.
- Jane Austen's (anonymous) novel Mansfield Park.
- Fanny Burney's last work, the historical novel The Wanderer: or, Female Difficulties.
- Lord Byron's tales in verse The Corsair (sells 10,000 copies on publication day (1 February) and over 25,000 in the first month, going through seven editions) and Lara (sells 6,000 copies on publication in the summer).
- Henry Cary's blank verse translation of Dante's Divine Comedy (complete).
- Walter Scott's (anonymous) first prose work, the historical novel Waverley (sells out within 2 days of publication (7 July)).
- William Wordsworth's long poem The Excursion.
- 7 January – Robert Nicoll, Scottish radical journalist and poet (died 1837)
- 21 April – Angela Burdett-Coutts, philanthropist (died 1906)
- 8 June – Charles Reade, novelist and dramatist (died 1884)
- 28 August – Sheridan le Fanu, Irish-born writer (died 1873)
- 3 September – James Joseph Sylvester, mathematician (died 1897)
- 7 September – William Butterfield, architect (died 1900)
- 28 December – John Bennet Lawes, agricultural scientist (died 1900)
- 27 January – Philip Astley, circus promoter (born 1742)
- 12 April – Charles Burney, music historian (born 1726)
- 12 July – William Howe, 5th Viscount Howe, general (born 1729)
- 19 July – Captain Matthew Flinders, explorer of the coasts of Australia (born 1774)
- 25 July – Charles Dibdin, composer (born 1745)
- 31 August – Arthur Phillip, admiral and first governor of New South Wales (born 1738)
- 18 November – William Jessop, civil engineer (born 1745)
- 22 November – Edward Rushton, abolitionist and pioneer of education for the blind (born 1756)
- 9 December – Joseph Bramah, inventor and locksmith (born 1748)
- Palmer, Alan; Veronica (1992). The Chronology of British History. London: Century Ltd. pp. 246–247. ISBN 0-7126-5616-2.
- "SV Queen". wrecksite. 2016-04-25. Retrieved 2016-11-26.
- Hadley Centre Ranked Central England temperature.
- Penguin Pocket On This Day. Penguin Reference Library. 2006. ISBN 0-14-102715-0.
- Weinreb, Ben; Hibbert, Christopher (1995). The London Encyclopaedia. Macmillan. p. 287. ISBN 0-333-57688-8.
- Higman, Chris (March 2014), "The Gas Light and Coke Company" (PDF), 200 Years of Commercial Gas Production, p. 5, retrieved 2014-05-20
- "Gas Light and Coke Co". Grace's Guide. 2014-05-16. Retrieved 2014-05-20.
- Maycock, R. J.; Silsbury, R. (2005). The Piers, Tramways and Railways at Ryde. Usk: Oakwood Press. p. 13. ISBN 0-85361-636-1.
- History of a Six Weeks' Tour.
- Jones, Neal T., ed. (1984). A Book of Days for the Literary Year. London; New York: Thames and Hudson. ISBN 0-500-01332-2.
- Cox, Michael, ed. (2004). The Concise Oxford Chronology of English Literature. Oxford University Press. ISBN 0-19-860634-6.