United Kingdom by-election records

Scope of these records

• Frequent interventions and withdrawals of parties in different seats.
• Frequent coalitions between parties, splits within parties and floor-crossing by members.
• Uncontested elections and truces between parties, in particular during both World Wars.
• Generally more significant competition from independent candidates and minor parties.
• Multi-member seats and university seats.
• Higher frequency of by-elections, partly due to the practice of often uncontested ministerial by-elections which ended in 1926.
• Generally higher turnouts, although several wartime elections exhibited the lowest recorded turnouts.
• Generally higher variation in size of constituency electorates.

Glossary

• Gain - victory by a party that was not victorious at the immediate previous election
• Loss - defeat of a party that was victorious at the immediate previous election
• Hold - victory by a party that was victorious at the immediate previous election
• Win - victory by a party. ambiguous term that could mean either a gain or a hold
• Incumbent - the party that held the seat at the immediately previous election, irrespective of any intervening change of candidate or candidate's change of party
• Third party - In England, since 1922, the "third party" has been the Liberal Party and its successor, the Liberal Democrats. Additionally, in Scotland and Wales the Scottish National Party and Plaid Cymru are also considered to be third parties. Prior to 1922, the third party was the Labour Party.
• Minor party - parties smaller than the third party
• Uncontested - an election where only one candidate is put forward. No votes are actually cast and the candidate is by definition the victor.

  Numerical records

Largest swings

Largest fall in percentage share of vote

Largest increase in percentage share of vote

Largest winning share of the vote

Lowest winning share of the vote

Lowest share of the vote

Major parties

Candidates winning fewer than ten votes

Smallest majorities

Turnout

Highest turnout

Turnout increased from general election

Lowest turnout

• 1942 Poplar South by-election: 9.3%
• 1941 Harrow by-election: 10.7%
• 1944 Camberwell North by-election: 11.2%

Most candidates

Fewest candidates

Candidate records

Durable by-election candidates

Major parties

Minor parties and independents

Pre-1945

• 1899 Oldham by-election in which he was not elected
• 1908 Manchester North West by-election where he was defeated
• 1908 Dundee by-election where he was elected
• 1917 Dundee by-election where he was re-elected.
• 1924 Westminster Abbey by-election in which he was unsuccessful

Former MPs making a comeback at a by-election

Former MPs failing in a by-election

• 2019 Brecon and Radnorshire by-election - Previous incumbent Chris Davies runs again after being removed by a recall petition and loses the seat to the Liberal Democrats.
• 2019 Newport West by-election - Former Conservative Tatton MP Neil Hamilton stands for the UK Independence Party, winning 8.6% of the votes.
• 2016 Richmond Park by-election - Incumbent Richmond Park MP Zac Goldsmith stands as an independent Conservative to protest against a third runway at Heathrow. He loses to the Liberal Democrats.
• 2008 Haltemprice and Howden by-election - Former Vale of Glamorgan MP Walter Sweeney stands as an independent, winning 1% of the votes.
• 2005 Cheadle by-election: Stephen Day fails to regain for the Conservatives a seat he lost by only 33 votes four years previously.
• 1997 Winchester by-election: Gerald Malone fails to regain the seat for the Conservatives, after losing by only 2 votes six months previously.
• 1993 Christchurch by-election: Robert Hayward loses one of the Conservatives' safest seats to the Liberal Democrats.
• 1990 Eastbourne by-election: Richard Hickmet fails to defend the seat for the Conservatives, after publicly stating that for electors not to support him would be a moral victory for the Provisional Irish Republican Army.
• 1989 Pontypridd by-election: Tom Ellis, former Labour and SDP MP, stands for the Social and Liberal Democrats, losing his deposit.
• 1986 Fermanagh and South Tyrone by-election: Owen Carron fails to regain the seat for Sinn Féin that he held 1981-83.
• 1982 Peckham by-election: Dick Taverne, former Labour and Democratic Labour MP, stands for the SDP, fails to take Labour seat.
• 1982 Gower by-election: Gwynoro Jones, former Labour MP, stands for the SDP, fails to take Labour seat.
• 1982 Beaconsfield by-election: Paul Tyler fails for the Liberals in a by-election held during the Falklands War.
• 1981 Warrington by-election: Roy Jenkins narrowly fails to win for the SDP from Labour in its first parliamentary contest.
• April 1981 Fermanagh and South Tyrone by-election: Harry West fails to regain his old seat against Bobby Sands
• 1978 Hamilton by-election: Margo MacDonald fails to repeat the SNP's 1967 triumph.
• 1978 Ilford North by-election: Thomas Iremonger, who had sat for the seat 1954-74, stands as an independent Conservative, winning a mere 1.5% of the vote.
• 1977 Birmingham Stechford by-election: Terry Davis loses a safe Labour seat.
• 1976 Walsall North by-election: David Winnick loses a safe Labour seat.
• 1971 Liverpool Scotland by-election: Peter Mahon stands as an Independent Labour Anti-Abortion candidate, securing 10.3% of the vote.
• 1969 Brighton Pavilion by-election: Thomas Skeffington-Lodge stands for Labour in a safe Conservative seat, 19 years after losing his seat.
• 1967 Nuneaton by-election: Air Vice-Marshal Donald Bennett stands as a National Party candidate, 22 years after losing his seat as a Liberal MP.
• 1965 Salisbury by-election: Horace Trevor-Cox stands as an independent Conservative, 20 years after losing his seat.
• 1965 Leyton by-election: Patrick Gordon Walker narrowly loses a supposed safe seat.
• 1962 South Dorset by-election: Angus Maude narrowly loses.
• 1960 Bolton East by-election: Frank Byers stands for the Liberals.
• 1956 Hereford by-election: Frank Owen fails to regain for the Liberals the seat he previously sat for 1929-1931.
• 1956 Mid Ulster by-election: Michael O'Neill fails to regain the seat, a year after retiring as its MP.
• 1948 Croydon North by-election: Air Vice-Marshal Donald Bennett stands for the Liberals, losing his deposit, and Harold Nicolson, for Labour, but fail to take a Conservative seat three years after both lost their respective seats.
• 1941 Hornsey by-election, 1941 Hampstead by-election and two others: Noel Pemberton Billing fails to take a seat, 20 years after standing down as an independent MP.
• 1924 Westminster Abbey by-election: Winston Churchill narrowly fails to take the seat, as a Constitutionalist.
• 1923 Anglesey by-election: Edward Thomas John failed to defend the seat.
• 1921 Woolwich East by-election: Ramsay MacDonald loses a supposed safe Labour seat.
• 1921 Westminster Abbey by-election: Arnold Lupton failed to take a Conservative seat, coming third, ten years after standing down.
• 1921 Cardiganshire by-election: W. Llewelyn Williams defeated in this race, as anti-Coalition Liberal contesting against a Coalition Liberal, three years after abolition of his previous seat.
• 1920 Dartford by-election: Thomas Edward Wing failed to defend the seat, over a year after losing his previous seat, losing it to Labour.

  Re-election of Ministers

• 1922 Pontypridd by-election Thomas Arthur Lewis was defeated after being appointed a Junior Lord of the Treasury.
• 1921 Dudley by-election Sir Arthur Griffith-Boscawen was defeated after being appointed Minister of Agriculture.
• 1914 Ipswich by-election Charles Masterman was defeated in a subsequent attempt to return to the House of Commons.
• 1914 Bethnal Green South West by-election Charles Masterman was defeated after being appointed Chancellor of the Duchy of Lancaster.
• 1912 Manchester South by-election Sir Arthur Haworth was defeated after being appointed a Junior Lord of the Treasury.
• 1911 North Ayrshire by-election Andrew Macbeth Anderson was defeated after being appointed Solicitor General for Scotland.
• 1908 Manchester North West by-election Winston Churchill was defeated after being appointed President of the Board of Trade
• 1905 Brighton by-election Gerald Loder was defeated after being appointed Lord Commissioner of the Treasury

  Shortest-serving by-election victors

Since 1945

• ¹ died
• ² defeated at next general election
• ³ disqualified
• ⁴ retired at next general election
• ⁵ retired at next general election due to personal difficulties
• ^a returned to Parliament at a subsequent election
• ^b had served previously as an MP

  Pre-1945

• Henry Francis Compton, Conservative 1905 New Forest by-election 46 days ²
• Ronald Bell, Conservative 1945 Newport by-election 70 days ^2a
• Donald Bennett, Liberal 1945 Middlesbrough West by-election 73 days ²
• John Dumphreys, Conservative 1909 Bermondsey by-election 83 days ²
• Seaborne Davies, Liberal 1945 Caernarvon Boroughs by-election 91 days ²
• Ruth Dalton, Labour 1929 Bishop Auckland by-election 92 days ³
• Joseph Ormond Andrews, Liberal 1905 Barkston Ash by-election 97 days ²
• Dr Robert McIntyre, SNP 1945 Motherwell by-election 104 days ²
• George Knox Anderson, Conservative 1918 Canterbury by-election 113 days ³
• Herbert Evans, Labour 1931 Gateshead by-election 121 days ¹
• Andrew Clarke, Labour 1929 Midlothian and Peebles Northern by-election 121 days ^2b
• Sir Henry Wilson, Unionist February 1922 North Down by-election 121 days ⁵
• Joseph Henderson, Labour 1931 Manchester Ardwick by-election 135 days ^2a
• Evan Cotton, Liberal 1918 Finsbury East by-election 151 days ²
• David Hardie, Labour 1931 Rutherglen by-election 159 days ²
• Lord Arthur Hill, Unionist 1907 West Down by-election 193 days ^7b
• Oswald Cawley, Liberal January 1918 Prestwich by-election 202 days ¹
• Francis Norie-Miller, Liberal National 1935 Perth by-election 212 days ³
• George Banton, Labour 1922 Leicester East by-election 230 days ^2a
• William Henry Somervell, Liberal 1918 Keighley by-election 232 days ²
• Noel Edward Buxton, Liberal 1905 Whitby by-election 238 days ^2a
• Leslie Orme Wilson, Conservative 1922 Portsmouth South by-election 243 days ^7b
• Leah Manning, Labour 1931 Islington East by-election 250 days ^2a
• Frederick William Gibbins, Liberal 1910 Mid Glamorgan by-election 253 days ³
• C. V. F. Palmer, Independent February 1920 The Wrekin by-election 261 days ¹
• Maurice Healy, Ind. Nationalist 1909 Cork City by-election 262 days ^2ab
• John Edward Sutton, Labour 1922 Manchester Clayton by-election 270 days ^2ab
• James Chuter Ede, Labour 1923 Mitcham by-election 278 days ^2a
• J. J. Cleary, Labour 1935 Liverpool Wavertree by-election 281 days ²
• Sir William Beveridge, Liberal 1944 Berwick-upon-Tweed by-election 282 days ²
• W. P. Sidney, Conservative 1944 Chelsea by-election 288 days ⁴
• Sir John Reith, National February 1940 Southampton by-election 293 days ⁶
• W. E. Gibbons, Conservative 1944 Bilston by-election 309 days ²
• Lord Charles Beresford, Conservative 1902 Woolwich by-election 320 days ^7ab
• Arthur Henderson, Labour 1923 Newcastle-upon-Tyne East by-election 323 days ^2ab
• James Henry Hall, Labour 1930 Whitechapel and St Georges by-election 328 days ^2a
• Thomas Naylor, Labour 1921 Southwark South East by-election 336 days ^2a
• ¹ died
• ² defeated at next general election
• ³ retired at next general election
• ⁴ retired at next general election, upon succession to a peerage
• ⁵ assassinated by IRA
• ⁶ elevated to the Peerage
• ⁷ resigned
• ^a returned to Parliament at a subsequent election
• ^b had served previously as an MP

  Youngest by-election victors

• Esmond Harmsworth, elected on 15 November 1919 from Isle of Thanet aged 21 years 170 days.
• Youngest woman: Bernadette Devlin, elected on 17 April 1969 from Mid Ulster aged 21 years 359 days.

  Babies of the House elected at by-elections

Oldest by-election victors

• John Benbow was 75 or 76 when he held the 1844 Dudley by-election for the Conservatives.
• Hucks Gibbs was 71 when he held the April 1891 City of London by-election for the Conservatives.
• Philip Manfield was 71 or 72 when he held the 1891 Northampton by-election for the Liberals.
• Sir Robert Pullar was 79 when he held the 1907 Perth by-election for the Liberals.
• David Cleghorn Hogg was 73 when he gained the 1913 Londonderry City by-election for the Liberals.
• Sir Swire Smith was 73 when he held the 1915 Keighley by-election for the Liberals.
• William Frederick Hicks Beach was 74 when he held the 1916 Tewkesbury by-election for the Conservatives.
• Sir George Reid was 70 when he held the 1916 St George's, Hanover Square by-election for the Conservatives. He was a former Prime Minister of Australia.
• Sir John Fleming was 69 or 70 when he held the 1917 Aberdeen South by-election for the Liberals.
• George Edwards was almost 70 when he gained the 1920 South Norfolk by-election for Labour. He was a former agricultural labourer.
• Henry Bruce Armstrong was almost 77 when he held the 1921 Mid Armagh by-election for the Ulster Unionists.
• William Nathaniel Jones was 70 when he held the 1928 Carmarthen by-election for the Liberals.
• Francis Norie-Miller was 76 when he gained the 1935 Perth by-election for the Liberal Nationals.
• James Little was 70 when he held the 1939 Down by-election for the Ulster Unionists.
• John Evans was 70 when he held the 1946 Ogmore by-election for Labour.

• John Blaquiere was 71 when he held the June 1803 Downton by-election for the Tories. He was previously MP for Rye in 1801-02.
• Bartholomew Bouverie was 73 when he held the 1826 Downton by-election for the Tories. He was previously MP for the same seat from 1819 until the general election earlier in 1826.
• Quintin Dick was 71 when he held the 1848 Aylesbury by-election for the Conservatives. He was previously MP for Maldon in 1830-47.
• James William Freshfield was 77 when he won the 1851 Boston by-election for the Conservatives. He was previously MP for Penryn and Falmouth in 1835-41.
• William Johnson Fox was 71 when he held the 1857 Oldham by-election for the Liberals. He was previously MP for the same seat from 1852 until the general election earlier in 1857.
• William Cubitt was 71 when he held the 1862 Andover by-election for the Conservatives. He was previously MP for the same seat in 1847-61.
• John Morgan Cobbett was 71 when he won the 1872 Oldham by-election for the Conservatives. He had been previously MP for the same seat as a Liberal in 1852-65.
• James Patrick Mahon was 79 when he held the 1879 Clare by-election and 87 when he held the 1887 County Carlow by-election for the Irish Nationalists.
• Isaac Holden was 75 when he held the 1882 West Riding of Yorkshire by-election for the Liberals. He had previously been MP for Knaresborough in 1865-68.
• Sir Wilfrid Lawson was 74 when he held the 1903 Camborne by-election for the Liberals. He had previously been MP for Cockermouth in 1886-1900.
• John Frederick Cheetham was 70 when he won the 1905 Stalybridge by-election for the Liberals. He had served previously as MP for North Derbyshire 1880-85 prior to that seat's abolition.
• Sir Alfred Hopkinson was 74 when he won the 1926 Combined English Universities by-election for the Conservatives. He had previously been MP for Cricklade 1895-98 before resigning.
• Arthur Salter was 70 when he held the 1951 Ormskirk by-election for the Conservatives. He had served previously as MP for Oxford University 1937-50 prior to that seat's abolition.

• Enoch Powell was 73 when he successfully defended his seat at the 1986 South Down by-election for the Ulster Unionists, after a protest resignation against the Anglo-Irish Agreement, although he had been an MP almost continuously since 1950.

  First women by-election victors

First ethnic minority by-election victors

• David Lammy held the 2000 Tottenham by-election for Labour.
• Mark Hendrick held the 2000 Preston by-election for Labour.
• Parmjit Singh Gill gained the 2004 Leicester South by-election for the Liberal Democrats.
• Seema Malhotra held the 2011 Feltham and Heston by-election for Labour, the first woman to win it.

First by-election victors from specific religions

• David Salomons was the first Jewish by-election victor, at the 1851 Greenwich by-election.
• Terry Rooney was the first Mormon by-election victor, at the 1990 Bradford North by-election.
• Parmjit Singh Gill became the first Sikh by-election victor, at the 2004 Leicester South by-election.
• Virendra Sharma became the first Hindu by-election victor, at the 2007 Ealing Southall by-election.
• Rosena Allin-Khan was the first Muslim by-election victor, at the 2016 Tooting by-election.

  Physically disabled by-election victors

• John Horne Tooke, who lost sight of an eye in a boyhood fight, won the 1801 Old Sarum by-election.
• Fulk Greville Howard, who lost sight of an eye in the Helder expedition in 1799, won the 1808 Castle Rising by-election.
• Sir William Carr Beresford, who lost sight of an eye in an accident on military service in 1786, won the 1811 County Waterford by-election.
• Samuel Shepherd, increasingly deaf from 1790, won the 1814 Dorchester by-election.
• Arthur MacMurrough Kavanagh, born without hands and feet, won the 1866 Wicklow County by-election.
• Michael Davitt, who lost his right arm in a factory accident in 1857, won the 1882 Meath by-election, although he was disqualified from sitting because he was in prison.
• Aubrey Herbert, who was almost blind from childhood, won the 1911 South Somerset by-election.
• John Dugdale, who was partly deaf from childhood, won the 1941 West Bromwich by-election.
• Cecil Manning, who lost his right arm in action in World War I, won the 1944 Camberwell North by-election.
• Hervey Rhodes, who walked with a limp since severe wounding in World War I, won the 1945 Ashton-under-Lyne by-election.
• William Rupert Rees-Davies, who lost his right arm in action in World War II, won the 1953 Isle of Thanet by-election.

  By-elections losers awarded seats on disqualification of winner

• Malcolm St Clair, 1961 Bristol South East by-election
• Charles Beattie, 1955 Mid Ulster by-election

  Two or more former MPs contest by-election

• 2008 Haltemprice and Howden by-election¹
• 1997 Winchester by-election
• 1986 Fermanagh and South Tyrone by-election
• 1982 Beaconsfield by-election
• 1981 Warrington by-election
• 1969 Brighton Pavilion by-election
• 1965 Salisbury by-election
• 1956 Mid Ulster by-election
• 1948 Croydon North by-election
• 1933 Altrincham by-election
• 1930 Glasgow Shettleston by-election
• 1930 Nottingham Central by-election
• 1928 Cheltenham by-election

Frequency and duration records

Longest period without a by-election

Longest period between a vacancy arising and a by-election writ being moved

• 1941 The Wrekin by-election: 357 days. James Baldwin-Webb was presumed killed as a result of enemy action when SS City of Benares was torpedoed on 17 September 1940; the writ was moved on 9 September 1941.
• 1941 King's Norton by-election: 327 days. Ronald Cartland was killed in action on 29–30 May 1940. Initially posted missing, his death was not presumed until January 1941. The writ was moved on 22 April 1941.
• 1941 Hitchin by-election: 272 days. Sir Arnold Wilson was presumed killed in action on 31 May 1940; the writ was moved on 27 February 1941.
• 1969 Newcastle-under-Lyme by-election: 236 days. Stephen Swingler died on 19 February 1969; the writ was moved on 13 October 1969.
• 1969 Swindon by-election: 220 days. Francis Noel-Baker resigned on 7 March 1969; the writ was moved on 13 October 1969.

  Longest period without a seat changing hands

Longest period between by-election gains for a party

Longest period between by-election holds for a party

• between holding the 1976 Newcastle-upon-Tyne Central by-election and the 1977 Grimsby by-election.
• between holding the 1967 Manchester Gorton by-election and the 1968 Sheffield Brightside by-election.
• between holding the 1967 Rhondda West by-election and the 1967 Manchester Gorton by-election.

  Longest period between by-election losses for a party

Longest period without an opposition gain

Most by-elections in one day

Most by-election losses in one day

Seats with more than one by-election in a single Parliament

• Bootle: May and November 1990.
• Fermanagh and South Tyrone: April and August 1981.
• Bristol South East: 1961 and 1963.
• Mid Ulster: 1955 and 1956.
• Edinburgh East: 1945 and 1947.
• Middlesbrough West: 1940 and 1945.
• Combined Scottish Universities: 1936, 1938 and 1945.
• Berwick-upon-Tweed: 1941 and 1944.
• Clay Cross: 1936 and 1944.
• West Derbyshire: 1938 and 1944.
• Buckingham: 1937 and 1943.
• Manchester Gorton: 1937 and 1942.
• Dunbartonshire: 1936 and 1941.
• Greenock: 1936 and 1941.
• Doncaster: 1938 and 1941.
• Southampton: February and November 1940.
• Preston: 1936 and 1940.
• Wandsworth Central: 1937 and 1940.
• City of London: 1938 and 1940.
• Combined Scottish Universities: 1934 and 1935.
• Eastbourne: 1932 and 1935.
• Twickenham: 1932 and 1934.
• Portsmouth South: 1922 and 1923.
• North Down: 1921, February and July 1922.
• West Down: 1921 and 1922.
• South Londonderry: 1921 and 1922.
• Louth: 1920 and 1921.
• The Wrekin: February and November 1920.
• Londonderry North: 1919 and 1922.
• Prestwich: January and October 1918.
• Edinburgh and St Andrews Universities: 1916 and 1917.
• St George's Hanover Square: 1913, 1916 and 1918.
• Portsmouth: 1912 and 1916.
• City of London: February and June 1906.
• Oswestry: 1901 and 1904.
• Southport: 1898 and 1899.
• City of London: April and June 1891.
• Buckingham: 1889 and 1891.
• Ayr Burghs: 1888 and 1890.
• Northampton: 1881, 1882 and 1884.
• Preston: 1881 and February and November 1882.
• Bath: May, June and October 1873.
• South Shropshire: 1866 and 1867.
• East Gloucestershire: January and December 1854.
• Greenwich: 1851 and 1852.
• South Nottinghamshire: 1848 and 1852.
• Buckinghamshire: 1837 and 1839 and 1842 and 1845, within two successive parliaments.

  Other seats with by-elections less than five years apart

• Hemsworth: 1991 and 1996.
• Upper Bann: 1986 and 1990.
• Belfast South: 1982 and 1986.
• Fermanagh and South Tyrone: August 1981 and 1986.
• Nuneaton: 1965 and 1967.
• Ormskirk: 1951 and 1953.
• Liverpool Wavertree: 1931 and 1935.
• Twickenham: 1929, 1932 and 1934.
• Westminster Abbey: 1921 and 1924.

  By-election days

Countermanded poll

Seats left vacant

Causes of by-elections

By-elections prompted by assassination

• 2016 Batley and Spen by-election: Jo Cox was killed by a white nationalist, 16 June 2016
• 1990 Eastbourne by-election: Ian Gow was killed by a Provisional IRA bomb under his car, 30 July 1990
• 1984 Enfield Southgate by-election: Sir Anthony Berry was killed in the Provisional IRA Brighton hotel bombing, 12 October 1984.
• 1982 Belfast South by-election: Rev. Robert Bradford was shot by the Provisional IRA, 14 November 1981.
• July 1922 North Down by-election: Field Marshal Sir Henry Wilson, Bt. was shot by the IRA outside his home, 22 June 1922.

  By-elections prompted by accidental death

• 2014 Heywood and Middleton by-election: Jim Dobbin died from alcohol poisoning.
• 2000 Romsey by-election: Michael Colvin was killed by a house fire.
• 1994 Eastleigh by-election: Stephen Milligan accidentally choked himself while attempting autoerotic asphyxia.
• 1994 Bradford South by-election: Bob Cryer was killed in a car crash.
• 1987 Truro by-election: David Penhaligon was killed in a car crash.
• 1980 Glasgow Central by-election: Thomas McMillan died from injuries received in falling from a bus.
• 1963 Rotherham by-election: Jack Jones was killed in a car crash.
• 1959 South West Norfolk by-election: Sidney Dye was killed in a car crash.
• 1958 Islington North by-election: Wilfred Fienburgh was killed in a car crash.
• 1957 Ipswich by-election: Richard Stokes died from injuries received in a car crash.
• 1953 North Down by-election: Sir Walter Smiles was killed in the MV Princess Victoria disaster during the storm surge.
• 1952 Dundee East by-election: Thomas Cook was killed in a car crash.
• 1948 Edmonton by-election: Evan Durbin was drowned while swimming.
• 1948 Stirling and Falkirk by-election: Joseph Westwood was killed in a car crash.
• 1948 Armagh by-election: Sir William Allen died from injuries received in a road accident.
• 1947 Liverpool Edge Hill by-election: Dr Richard Clitherow died due to an overdose of barbiturates after he had been "run down and jaded".
• 1947 Jarrow by-election: Ellen Wilkinson was killed by an accidental overdose of medication.
• 1946 Glasgow Cathcart by-election: Francis Beattie was killed in a car crash.
• 1945 Smethwick by-election: Alfred Dobbs was killed in a car crash.
• 1945 Motherwell by-election: James Walker was killed in a road accident.
• 1944 Bury St Edmunds by-election: Lieut-Col. Frank Heilgers was killed in a train crash.
• 1942 Manchester Clayton by-election: John Jagger was killed in a motorcycle accident.
• 1939 Stretford by-election: Anthony Crossley was killed in an air crash.
• 1933 Hitchin by-election: Viscount Knebworth was killed in a plane crash.

  By-elections prompted by suicide

• 1997 Paisley South by-election: Gordon McMaster committed suicide.
• 1990 Mid Staffordshire by-election: John Heddle committed suicide.
• 1982 Birmingham Northfield by-election: Jocelyn Cadbury committed suicide.
• August 1981 Fermanagh and South Tyrone by-election: Bobby Sands continued his hunger strike until death.
• 1968 Acton by-election: Bernard Floud committed suicide.
• 1960 Harrow West by-election: Sir Albert Braithwaite committed suicide.
• 1949 Leeds West by-election: Thomas Stamford committed suicide.
• 1946 Heywood and Radcliffe by-election: John Whittaker committed suicide.
• 1940 City of Chester by-election: Sir Charles Cayzer committed suicide after killing his butler.
• 1939 Wells by-election: Anthony Muirhead committed suicide.
• 1932 Eastbourne by-election: Edward Marjoribanks committed suicide.

  By-elections prompted by posthumous election of MP

• 1945 Bromley by-election: Sir Edward Taswell Campbell died before his election declaration at the 1945 general election.
• 1945 Monmouth by-election: Leslie Pym died before his election declaration at the 1945 general election.
• 1935 Combined Scottish Universities by-election: Noel Skelton died before his election declaration at the 1935 general election.
• 1906 North Galway by-election: Thomas Higgins died before his election declaration at the 1906 general election.

  By-elections prompted by scandal

• 2019 Brecon and Radnorshire by-election: the seat was declared vacant after Chris Davies pleaded guilty to filing false expenses claims, and a recall petition was successful.
• 2019 Peterborough by-election: the seat was declared vacant after Fiona Onasanya was convicted of perverting the course of justice in relation to motoring penalty points issued in 2017. This was the first successful recall petition under the provisions of the Recall of MPs Act 2015.
• 2018 West Tyrone by-election: Barry McElduff resigned after becoming embroiled in a social media controversy.
• 2014 Newark by-election: Patrick Mercer resigned after being suspended from the House of Commons for six months by the Parliamentary Standards Committee for asking parliamentary questions in exchange for money.
• 2013 Eastleigh by-election: Chris Huhne resigned after pleading guilty to perverting the course of justice in relation to persuading his wife to accept motoring penalty points in 2003.
• 2012 Rotherham by-election: Denis MacShane resigned after House of Commons Standards and Privileges Committee recommended he be suspended from the service of the House for twelve months; their inquiry arose from the United Kingdom Parliamentary expenses scandal.
• 2011 Barnsley Central by-election: Eric Illsley resigned after pleading guilty to charges of false accounting arising from the United Kingdom Parliamentary expenses scandal.
• 2009 Glasgow North East by-election: Michael Martin resigned as Speaker rather than face a vote of no-confidence, amid criticism of his actions arising from the United Kingdom Parliamentary expenses scandal.
• 2009 Norwich North by-election: Ian Gibson resigned after being debarred as a Labour candidate, due to allegations arising from the United Kingdom Parliamentary expenses scandal.
• 1997 Beckenham by-election: Piers Merchant resigned after a newspaper story revealed that his previous denials of an affair were lies.
• 1977 Bournemouth East by-election: John Cordle resigned after he was criticised by a Select Committee for business links to corrupt architect John Poulson.
• 1976 Walsall North by-election: John Stonehouse resigned after being convicted of insurance fraud.
• 1973 Berwick-upon-Tweed by-election: Antony Lambton resigned after his visits to prostitutes and use of cannabis were exposed by the News of the World.
• 1963 Stratford-upon-Avon by-election: John Profumo resigned after his denials of an affair with Christine Keeler were shown to be lies.
• 1959 Harrow East by-election: Ian Harvey resigned after conviction for gross indecency with a guardsman in Hyde Park.
• 1953 Paddington North by-election: Bill Field resigned after conviction for importuning for immoral purposes in a public lavatory.
• 1949 Sowerby by-election: John Belcher resigned after being found to have accepted gifts from businessmen for political favours.
• 1941 Scarborough and Whitby by-election: Sir Paul Latham resigned after he was arrested to be tried by court-martial on 13 charges of disgraceful conduct.
• 1936 Derby by-election: James Henry Thomas resigned after being found to have disclosed budget secrets.
• 1936 Balham and Tooting by-election: Sir Alfred Butt resigned after being found to have disclosed budget secrets.
• 1931 Pontypridd by-election: Thomas Mardy Jones resigned after being found to have abused a travel voucher.
• 1926 Buckrose by-election: Guy Gaunt resigned after being cited as co-respondent in a divorce case.

  By-elections prompted to provide seat for seat-less personality

• 1965 Nuneaton by-election: For Frank Cousins.
• 1965 Leyton by-election: For Patrick Gordon-Walker.
• 1950 Sheffield Neepsend by-election: For Frank Soskice.
• February 1940 Southampton by-election: For Sir John Reith.
• 1940 Wandsworth Central by-election: For Ernest Bevin.
• 1922 Portsmouth South by-election: For Leslie Orme Wilson.
• February 1906 City of London by-election: For Arthur Balfour.
• 1896 Montrose Burghs by-election: For John Morley.

  By-elections prompted by party disputes and defections

By-elections resulting from Members resigning on principle

• 2016 Richmond Park by-election: Zac Goldsmith resigned to force a by-election on the issue of the expansion of Heathrow Airport, and contested as an Independent. He was defeated by Sarah Olney of the Liberal Democrats. Goldsmith later regained his seat the following year at the 2017 general election.
• 2008 Haltemprice and Howden by-election: David Davis resigned to force a by-election on the issue of civil liberties. He was re-elected with neither of the other main parties contesting the seat.
• 1986 Northern Ireland by-elections: Fifteen Unionist MPs resigned and re-contested their seats in protest at the Anglo-Irish Agreement. All but one was re-elected.
• 1963 Bristol South East by-election: Malcolm St Clair honoured a pledge to stand down if law changed to allow Tony Benn to disclaim his peerage.
• 1938 Kinross-shire and Perthshire by-election: The Duchess of Atholl resigned in protest at Neville Chamberlain's appeasement policy and sought re-election. She was defeated.
• 1927 Southwark North by-election: Leslie Haden-Guest resigned from the Labour Party over its policy on China, and re-contested the seat as an Independent Constitutionalist with Conservative support. He was defeated, finishing bottom of the poll. The Liberals gained the seat.
• 1927 Edinburgh Leith by-election: William Wedgwood Benn resigned following his resignation from the Liberal party and joining the Labour Party. He did not contest the by-election out of fairness to the existing Labour candidate. The seat was narrowly held by a new Liberal candidate.
• 1914 Cork City by-election: William O'Brien resigned to submit himself to the voters after the Irish Nationalists had made council gains in Cork. He was returned unopposed.
• 1912 Bow and Bromley by-election: George Lansbury resigned to contest his seat on the issue of Women's Suffrage, although he was disenchanted with a range of Labour party policies. He was defeated.
• 1909 Stratford-on-Avon by-election: Thomas Kincaid-Smith resigned from the Liberal Party on the issue of compulsory national service. He stood as an Independent with National Service League support. He was defeated, finishing bottom of the poll.
• 1906 Mid Cork by-election: D. D. Sheehan resigned and re-contested his seat following his expulsion from the Irish Nationalist group for not signing the party pledge. Re-elected as an independent.

  By-elections prompted by Member's desire to contest another seat

• 1918 East Tyrone by-election: William Redmond resigned in order to defend his late father's seat at Waterford City. He was successful.
• 1914 East Worcestershire by-election: Austen Chamberlain resigned in order to defend his late father's seat at Birmingham West. He was successful.
• 1911 East Wicklow by-election: John Muldoon resigned in order to contest the East Cork by-election. He was successful.

  By-elections caused by the previous result being declared void

• 2011 Oldham East and Saddleworth by-election: The result of the 2010 general election was declared void because the victor was found guilty of knowingly making false statements about a rival candidate.
• 1997 Winchester by-election: The result of the 1997 general election was declared void because ballot papers which had not received the official mark would have affected the result, if counted. Liberal Democrat Mark Oaten massively increased the minute majority he had achieved in the general election.
• 1924 Oxford by-election: The result of the 1923 general election was declared void because there were irregularities in the election expenses of the successful candidate.
• 1923 Berwick-upon-Tweed by-election: The result of the 1922 general election was declared void because there were irregularities in the election expenses of the successful candidate.
• 1911 North Louth by-election: The result of the December 1910 general election was declared void because of corrupt practices and bribery on the part of the successful candidate.

  By-elections prompted by disqualification of the sitting Member

• 1961 Bristol South East by-election: Tony Benn had inherited a Peerage from his father. Although by-elections were routinely called where Members had succeeded to the Peerage, the seat was not considered vacated until the Member had received a Writ of Summons to the House of Lords, and Benn, who refused to accept the Peerage, did not apply for one. The seat was declared vacant by a resolution of the House of Commons.
• 1956 Mid Ulster by-election: Charles Beattie was found to be disqualified through membership of National Assistance panels. A bill indemnifying him from the consequences of acting as an MP while disqualified was passed by the House of Commons; Beattie did not stand in the by-election.
• 1955 Mid Ulster by-election: Tom Mitchell was disqualified as a felon.
• 1950 Belfast West by-election: Rev James Godfrey MacManaway was found by the Judicial Committee of the Privy Council to be disqualified, as a Minister of the Church of Ireland.
• 1925 Walsall by-election: William Preston was found to be disqualified owing to his holding government contracts. A bill indemnifying him was passed by the House of Commons and Preston was re-elected at the by-election.
• 1924 Dover by-election: John Astor was disqualified for voting before he took the oath. He was returned unopposed at the by-election.
• 1913 Whitechapel by-election: Sir Stuart Samuel was found to be disqualified owing to his holding government contracts. A bill indemnifying him was passed by the House of Commons and Samuel was narrowly re-elected at the by-election.
• 1904 City of London by-election: Alban Gibbs was found to be disqualified owing to his holding government contracts. Gibbs resigned and was re-elected unopposed at the by-election.
• 1904 St Albans by-election: Vicary Gibbs was found to be disqualified owing to his holding government contracts. Gibbs resigned and was narrowly defeated at the by-election.

  By-elections prompted by expulsion from the House

• 1955 South Norfolk by-election: Peter Baker was expelled after being convicted of uttering forged documents.
• 1947 Gravesend by-election: Garry Allighan was expelled after being found to be in extreme contempt of the House by his peers.
• 1922 Hackney South by-election: Horatio Bottomley was expelled after being convicted of fraud, perjury and false accounting.
• 1903 Galway Borough by-election: the seat was declared vacant after Arthur Alfred Lynch was convicted of high treason.

  By-elections prompted by lunacy

• 1916 Colne Valley by-election: Charles Leach was adjudged a lunatic and his seat declared vacant.

  By-elections prompted by bankruptcy

• 1928 Ashton-under-Lyne by-election: Cornelius Homan lost his seat after being declared bankrupt.
• 1922 Camberwell North by-election: Henry Newton Knights lost his seat after being declared bankrupt.
• 1914 North Galway by-election: Richard Hazleton resigned before being declared bankrupt. He discharged his bankruptcy and was returned in the by-election.
• 1912 Hackney South by-election: Horatio Bottomley resigned after filing a bankruptcy petition.
• 1909 South Kilkenny by-election: Nicholas Joseph Murphy was declared bankrupt.

  By-elections prompted for miscellaneous reasons

• 1916 Widnes by-election: William Hall Walker resigned to permit him to donate his thoroughbred racing stock to create a National Stud in an "arms-length" transaction. He was returned unopposed at the by-election.

  By-elections prompted by death of member on wartime active service

Second World War

• 1945 Chelmsford by-election: John Macnamara was killed in action fighting in Italy.
• 1944 Berwick-upon-Tweed by-election: George Charles Grey was killed in action fighting in Normandy, France.
• 1944 Bury St Edmunds by-election: Frank Heilgers was killed in a train crash in Ilford.
• 1943 Acton by-election: Hubert Duggan died of tuberculosis contracted on active service. ^a
• 1943 Darwen by-election: Stuart Russell died of fever on active service in Egypt.
• 1943 Chippenham by-election: Victor Cazalet was killed in a plane crash in Gibraltar while escorting General Sikorski.
• 1943 Birmingham Aston by-election: Edward Orlando Kellett was killed in action fighting in North Africa.
• 1943 Buckingham by-election: John Whiteley was killed in a plane crash in Gibraltar while escorting General Sikorski.
• 1943 Bristol Central by-election: Lord Apsley was killed in action in a plane crash in the Middle-East.
• 1943 King's Lynn by-election: Somerset Maxwell died of wounds received at the Battle of El Alamein.
• 1942 Salisbury by-election: James Despencer-Robertson died suddenly, apparently from overwork as military secretary at Southern Command Headquarters. ^b
• 1942 Llandaff and Barry by-election: Patrick Munro died while taking part in an exercise for the Home Guard at Westminster.
• 1941 The Wrekin by-election: James Baldwin-Webb drowned when the SS City of Benares was torpedoed.
• 1941 Dudley by-election: Dudley Joel was killed in action while serving with the Royal Navy.
• 1941 Bodmin by-election: John Rathbone was killed in action on bombing operations over Germany.
• 1941 Hitchin by-election: Sir Arnold Wilson was killed in action over northern France while a gunner in Bomber Command
• 1941 King's Norton by-election: Ronald Cartland was killed in action during the retreat to Dunkirk.
• 1940 Manchester Exchange by-election: Peter Eckersley was killed in action in a plane crash while serving with the Fleet Air Arm.
• 1940 Heywood and Radcliffe by-election: Richard Porritt was killed in action fighting in Belgium.
• 1939 Wells by-election: Anthony Muirhead committed suicide owing to his fear that a leg-injury might prevent his service in the War. ^b

  First World War

• October 1918 Prestwich by-election: Oswald Cawley had been killed in action in France.
• 1918 Bath by-election: Lord Alexander Thynne had been killed in action in France.
• 1918 Canterbury by-election: Francis Bennett-Goldney had been killed by an on-duty car accident in France.
• 1918 Ross by-election: Percy Clive had been killed in action in France.
• 1918 Manchester South by-election: Philip Glazebrook had been killed in action in Palestine.
• 1917 Wisbech by-election: The Hon Neil Primrose died of wounds received in Palestine.
• 1917 Spalding by-election: The Hon Francis McLaren had been killed in a flying accident serving with the Royal Flying Corps.
• 1917 East Clare by-election: Willie Redmond had been killed in action in Belgium.
• 1917 Henley by-election: Valentine Fleming had been killed in an air raid in France.
• 1916 North Ayrshire by-election: Duncan Frederick Campbell had died in England of wounds received from a landmine on the Western Front.
• 1916 Winchester by-election: The Hon Guy Baring had been killed in the Battle of the Somme in France.
• 1916 Tewkesbury by-election: Michael Hicks Beach, Viscount Quenington had died of wounds in Egypt.
• 1915 St Austell by-election: The Hon Thomas Agar-Robartes had died of wounds received in the Battle of Loos in France.
• 1915 Cardiff by-election: Lord Ninian Crichton-Stuart had been killed in action in France.
• 1915 Uxbridge by-election: The Hon Charles Thomas Mills had been killed in action in France.
• 1915 Heywood by-election: Harold Thomas Cawley had been killed in action in the Battle of Gallipoli.
• 1915 Kilmarnock Burghs by-election: William Glynne Charles Gladstone had been killed in action in France.
• 1915 Mid Antrim by-election: The Hon Arthur O'Neill had been killed in action in the Ypres Salient in Belgium.

  Miscellaneous records

Incumbents fall directly from first place to third place

• 1995 Littleborough and Saddleworth by-election Conservatives loss, gained by the Liberal Democrats
• 1995 Perth and Kinross by-election Conservative loss, gained by the SNP
• 1994 Eastleigh by-election Conservative loss, gained by the Liberal Democrats
• 1985 Brecon and Radnor by-election Conservative loss, gained by the Liberals
• 1982 Mitcham and Morden by-election¹ Labour loss, gained by the Conservatives
• 1958 Rochdale by-election Conservative loss, gained by Labour
• 1934 Merthyr by-election ILP loss, gained by Labour
• 1929 Holland with Boston by-election Conservative loss, gained by the Liberals
• 1927 Bosworth by-election Conservative loss, gained by the Liberals
• 1926 Hull Central by-election² Liberal loss, gained by Labour
• 1920 South Norfolk by-election Liberal loss, gained by Labour

  Incumbent Government gains seats

Principal Opposition loses seats

Conservative

• 2000 Romsey by-election, lost to the Liberal Democrats
• 1969 Mid Ulster by-election,, lost to Unity
• 1965 Roxburgh, Selkirk and Peebles by-election, lost to the Liberals
• 1930 Paddington South by-election¹, lost to the Empire Free Trade Crusade
• 1924 Liverpool West Toxteth by-election, lost to Labour

  Labour

• 2017 Copeland by-election, lost to the Conservatives
• 2012 Bradford West by-election, lost to Respect
• 1988 Glasgow Govan by-election, lost to the SNP
• 1987 Greenwich by-election, lost to the SDP
• 1983 Bermondsey by-election, lost to the Liberals
• 1982 Mitcham and Morden by-election, lost to the Conservatives
• 1973 Glasgow Govan by-election, lost to the SNP
• 1973 Lincoln by-election, lost to Lincoln Democratic Labour
• 1972 Rochdale by-election, lost to the Liberals
• 1961 Bristol South-East by-election¹, awarded to the Conservatives
• 1960 Brighouse and Spenborough by-election, lost to the Conservatives
• 1953 Sunderland South by-election, lost to the Conservatives
• 1927 Southwark North by-election, lost to the Liberals
• 1923 Anglesey by-election², lost to the Liberals
• 1921 Woolwich East by-election, lost to the Coalition Conservatives

  By-election holds overturned at next general election

By-election victors had not contested previous general election

• 2014 Rochester and Strood by-election, gained by UKIP
• 2014 Clacton by-election, gained by UKIP
• 2000 South Antrim by-election, gained by the DUP
• 1995 North Down by-election, gained by the UK Unionists
• 1982 Glasgow Hillhead by-election, gained by the SDP ¹
• 1981 Crosby by-election, gained by the SDP ¹
• 1973 Isle of Ely by-election, gained by the Liberals
• 1973 Lincoln by-election, gained by Lincoln Democratic Labour ²
• 1969 Mid Ulster by-election, gained by Unity
• 1967 Hamilton by-election, gained by the SNP
• 1958 Torrington by-election, gained by the Liberals
• 1945 Chelmsford by-election, gained by Common Wealth
• 1945 Motherwell by-election, gained by the SNP
• 1944 Skipton by-election, gained by Common Wealth
• 1943 Eddisbury by-election, gained by Common Wealth
• 1943 Belfast West by-election, gained by the Northern Ireland Labour Party
• 1936 Ross and Cromarty by-election, gained by National Labour
• 1936 Combined Scottish Universities by-election, gained by National Labour
• 1934 Merthyr by-election, gained by Labour
• 1930 Paddington South by-election, gained by Empire Free Trade Crusade
• 1929 Liverpool Scotland by-election, gained by Labour
• 1926 Kingston upon Hull Central by-election, gained by Labour
• 1921 Kirkcaldy Burghs by-election, gained by Labour
• 1921 Woolwich East by-election, gained by the Coalition Conservatives

Victory from third or lower place

• 2012 Bradford West by-election, gained by Respect, from fifth place
• 2004 Leicester South by-election, gained by the Liberal Democrats, from third place
• 2003 Brent East by-election, gained by the Liberal Democrats, from third place
• 1988 Glasgow Govan by-election, gained by the SNP, from fourth place
• 1987 Greenwich by-election, gained by the SDP, from third place
• 1985 Brecon and Radnor by-election, gained by the Liberals, from third place
• 1983 Bermondsey by-election, gained by the Liberals, from third place
• 1981 Croydon North West by-election, gained by the Liberals, from third place
• 1973 Glasgow Govan by-election, gained by the SNP, from third place
• 1973 Berwick-upon-Tweed by-election, gained by the Liberals, from third place
• 1973 Ripon by-election, gained by the Liberals, from third place
• 1972 Sutton and Cheam by-election, gained by the Liberals, from third place
• 1966 Carmarthen by-election, gained by Plaid Cymru, from third place
• 1962 Orpington by-election, gained by the Liberals, from third place
• 1929 Holland with Boston by-election, gained by the Liberals, from third place

  Incumbent party did not contest

• 2016 Richmond Park by-election
• 1995 North Down by-election
• 1963 Bristol South East by-election
• 1942 Cardiff East by-election
• 1940 City of London by-election
• February 1940 Southampton by-election
• 1938 Combined Scottish Universities by-election
• 1936 Ross and Cromarty by-election
• 1936 Combined Scottish Universities by-election
• 1935 Perth by-election
• 1929 Liverpool Scotland by-election
• 1929 Preston by-election

  Losers had been unopposed at previous election

• 1930 Paddington South by-election Conservative loss, gained by Empire Free Trade Crusade.
• 1929 Liverpool Scotland by-election Irish Nationalist loss, gained by Labour.¹
• 1928 Halifax by-election Speaker loss, gained by Labour.²
• 1921 Kirkcaldy Burghs by-election Coalition Liberal loss, gained by Labour.
• 1921 Woolwich East by-election Labour loss, gained by Conservative.
• February 1920 The Wrekin by-election Coalition Liberal loss, gained by Independent.

Major party did not run

Great Britain

Northern Ireland

Victories by minor parties

• 2014 Rochester and Strood by-election - UKIP wins second elected MP victory following Clacton result.
• 2014 Clacton by-election - UKIP wins first elected MP victory following numerous second places in by-elections.
• 2012 Bradford West by-election - Respect candidate George Galloway delivers the party's first by-election gain.
• 2006 Blaenau Gwent by-election - Independent candidate, election agent of the previous incumbent, won with 46.7%.
• 1995 North Down by-election - UK Unionist Party candidate won with tacit backing of Democratic Unionist Party
• 1986 North Down by-election - Ulster Popular Unionist Party candidate won without Unionist opposition.
• Fermanagh and South Tyrone by-elections, August and April 1981 - Anti H-Block candidates linked to Sinn Féin won.
• 1973 Lincoln by-election - Lincoln Democratic Labour Association, incumbent MP held seat in new party colours.
• 1969 Mid Ulster by-election - Unity candidate won without Irish Nationalist opposition.
• 1956 Mid Ulster by-election - Independent Unionist candidate won without Unionist opposition.
• 1946 Glasgow Bridgeton by-election - Independent Labour Party candidate held seat.

  Minor parties other strong performance

Miscellaneous notable results

• The 2019 Brecon and Radnorshire by-election saw Labour finish fourth behind the Liberal Democrats, Conservatives and Brexit Party, barely holding its deposit. In addition, UKIP fell to last place, behind even the Official Monster Raving Loony Party – a result compared to the continuing SDP's defeat in the 1990 Bootle by-election.
• The 2016 Richmond Park by-election was the first Liberal Democrat gain since 2010, showing tentative signs of recovery for the party. It also gave them a female MP for the first time in the 56th parliament. In addition it was the first occasion in more than a century of Labour losing their deposit in a London by-election.
• The 2014 Clacton by-election saw the election of the first UKIP MP on the largest swing ever against the Conservative Party. It was also the first time that a party had gained a seat not having contested the previous election since the 1973 Isle of Ely by-election. The Liberal Democrat's 1.4% of the vote was their worst result in an English seat since 1924.
• The 2013 Eastleigh by-election delivered several records. It was the first time in an English seat that both Labour and Conservative finished outside of the top two. For the first time, UKIP came close to winning a seat. It was the closest three-cornered English by-election since the 1921 Penistone by-election, and, aside from the 1946 Combined English Universities by-election, it was won with the lowest winning share of the vote since 1918. Aside from the contrived example of the 1989 Richmond by-election it was also the first time Labour had finished fourth in a by-election while in Opposition.
• At the 2012 Rotherham by-election, the Conservative party fell from second to fifth place while the Liberal Democrats fell from third place to eighth, the lowest ranking ever achieved by a major party in a by-election. This followed the 2011 Barnsley Central by-election, where the Liberal Democrats took sixth place, dropping from second at the 2010 general election. The Rotherham by-election was also the first recorded by-election result to have women in the top four places.
• In the 2009 Glasgow North East by-election and 1999 Hamilton South by-election the Liberal Democrats came sixth in both cases, equalling the worst ever placing by a major party in the UK. In 1999 the party had 634 votes while in Glasgow the party won 474 votes.
• At the 2008 Henley by-election the Labour Party finished in fifth place, the worst ranking for the party in its history, and a record low for any government in a UK mainland constituency. The lowest ever for an incumbent government was the 1990 Upper Bann by-election when the Conservatives came sixth, although they had not previously contested the seat.
• At the 2006 Blaenau Gwent by-election, held on the same day as Bromley and Chislehurst, the Conservative Party's fifth-place ranking equalled the worst-place achieved by a major party in England or Wales, a feat the Conservatives had first achieved in the same seat in the 2005 general election. The Blaenau victor, Dai Davies was the first independent to hold a seat previously occupied by an independent since Sir C.V.F. Townshend held The Wrekin in 1920.
• The drop in the Conservative share of the vote, 11.1%, at the 2006 Bromley and Chislehurst by-election was their worst result in a Conservative-held seat while in opposition since 1930¹. At the same by-election, the Labour Party's fall from second to fourth place was the first time the party had suffered such a reverse in an English seat.
• The Conservative Party fell from second to fourth place in the 2004 Hartlepool by-election and fell from third to fourth place in the 1991 Liverpool Walton by-election. At the time their worst ranking in an English by-election since at least 1945 was the drop from third place to fourth place in the 1974 Newham South by-election, whilst the also dropped to fourth place in the 1983 Bermondsey by-election.
• The Labour party fell from second to fourth place in the 2000 Ceredigion by-election.
• At the Bootle by-election, 1990 the "continuing" SDP finished seventh out of eight candidates, behind the Monster Raving Loony Party, in a seat parts of which had once been in adjoining Crosby, scene of the party's greatest triumph only eight years previously.
• The Labour Party achieved fourth place in the 1989 Richmond by-election although this was contrived somewhat by the Social and Liberal Democrats and Social Democratic Party parties running separate candidates.
• At the 1976 Walsall North by-election, the Liberal Party could take only fifth place. Beaten by an independent and a minor party candidate, at the time, this was the worst placing for any major party in an English by-election since at least 1945.
• The last time the Liberals lost a by-election they were defending was at the 1957 Carmarthen by-election, defeated by the former Liberal MP turned Labour candidate, Lady Megan Lloyd-George. The Liberal parliamentary contingent was thus reduced to five MPs, its lowest ever level.

By-elections having national significance

• 2017 Copeland by-election: A Conservative win in a previously safe Labour seat confirmed the party's strong opinion poll lead and prompted an early election.
• 2016 Richmond Park by-election: After losing most of its seats in the 2015 general election, a Lib Dem gain on a large swing in a strongly Remain seat marked the beginning of a turnaround for the party and demonstrated the political effects of Brexit.
• 2014 Clacton by-election: The first by-election victory for the United Kingdom Independence Party
• 2008 Crewe and Nantwich by-election: A Conservative gain at a by-election for the first time since 1982, and the first time as an opposition party since 1978, demonstrated the Conservatives were back in contention to possibly win the next general election.
• 2003 Brent East by-election: A Lib Dem gain of a Labour safe seat on a 29% swing demonstrated the political effect of public dissatisfaction with the Iraq War.
• 1997 Wirral South by-election: A Labour gain on a large swing just weeks before a general election confirmed the move in the party's favour was real and meant the Conservatives became a minority government.
• 1991 Liverpool Walton by-election: The Militant group, as Walton Real Labour, opposed a Labour candidate for the first time; their showing led to the decision to re-organise as Militant Labour without using entryist tactics.
• May 1990 Bootle by-election: Abysmal showing of the 'continuing SDP' led to the party being wound up.
• 1987 Greenwich by-election: Defeat of a left-wing Labour candidate demonstrated the party's vulnerability.
• 1983 Darlington by-election: Labour's successful defence of a marginal seat stabilised the party, and secured the position of Leader Michael Foot.
• 1981 Crosby by-election: Victory of the Social Democratic Party in a rock-solid Conservative seat showed the national appeal of the party.
• April 1981 Fermanagh and South Tyrone by-election: Election of Maze prison hunger-striker Bobby Sands demonstrated that nationalist voters could support violent Republican candidates; taken by the Republican movement as a vindication of their stance, it led to the return of Sinn Féin as a major force in Northern Irish politics.
• 1977 Birmingham Stechford by-election: The loss of the seat to the Conservatives tipped Labour under James Callaghan into minority government status, necessitating the Lib-Lab Pact.
• 1967 Hamilton by-election: Scottish National Party victory massively boosted the prospects of the party.
• 1966 Kingston upon Hull North by-election: Easy Labour victory in a marginal seat demonstrated to Prime Minister Harold Wilson that he would probably win a snap general election, and led to the construction of the Humber Bridge.
• 1965 Roxburgh, Selkirk and Peebles by-election: Rare Conservative loss in Opposition leads to resignation of leader Sir Alec Douglas-Home and election of Edward Heath as first democratically elected Conservative leader.
• 1965 Leyton by-election: Foreign Secretary Patrick Gordon-Walker, who was found the seat after losing Smethwick in 1964, is again defeated; he is forced to resign from the Government.
• 1963 Kinross and Western Perthshire by-election: Prime Minister Sir Alec Douglas-Home successfully returned to the House of Commons after disclaiming his peerage.
• 1962 Orpington by-election: A Liberal gain in a suburban seat led to a national revival for the party.
• 1961 Bristol South East by-election: Incumbent Labour MP Tony Benn re-elected after inheriting a peerage; the seat was awarded to the defeated Conservative, but the circumstances led to the Peerage Act 1963 allowing hereditary peerages to be disclaimed.
• 1938 Oxford by-election: After a campaign dominated by appeasement and the Munich agreement, the government candidate won.
• 1935 Liverpool Wavertree by-election: Intervention of Independent Conservative Randolph Churchill, on platform of rearmament and anti-Indian Home Rule, hands safe seat to Labour on largest ever swing. Indication of hostility to National Government, and Prime Minister Ramsay MacDonald resigns within months.
• 1933 Fulham East by-election: Unexpected Labour gain in a previously safe Conservative constituency, ascribed to pacifism.
• 1922 Newport by-election: Election of an anti-Coalition Conservative in a tight three-way contest spurred on Conservative MPs to end their coalition with David Lloyd George.
• 1920 Dartford by-election: massive swing to Labour prefigures the party's eclipse of the Liberals.

  Firsts and lasts

• First by-election to be called via the provisions of the Recall of MPs Act 2015: 2019 Peterborough by-election
• Last Conservative gain in a by-election: 2017 Copeland by-election
• Last Labour gain at a by-election: 2012 Corby by-election
• Last Liberal Democrat gain at a by-election: 2019 Brecon and Radnorshire by-election
• First UK Independence Party gain at a by-election: 2014 Clacton by-election
• Last UK Independence Party gain at a by-election: 2014 Rochester and Strood by-election
• First by-election gain by a Northern Ireland party: 1943 Belfast West by-election
• Last by-election gain by a Northern Ireland party: 2000 South Antrim by-election
• First by-election gain by the Social Democratic Party : 1981 Crosby by-election
• Last by-election gain by the Social Democratic Party : 1987 Greenwich by-election
• Last by-election gain by the Liberal Party: 1986 Ryedale by-election
• First by-election gain by the Scottish National Party: 1945 Motherwell by-election
• Last by-election gain by the Scottish National Party: 2008 Glasgow East by-election
• First and last by-election gain by Plaid Cymru: 1966 Carmarthen by-election
• Last unopposed by-election in England, Scotland or Wales: 1946 Hemsworth by-election
• Last by-election in a university constituency: 1946 Combined Scottish Universities by-election
• Last by-election caused by appointment to ministerial office: 1926 East Renfrewshire by-election
• Last by-election from what was to become the Irish Free State: 1919 Dublin University by-election
• Last double member by-election: 1920 Stockport by-election
• Last by-election result to be declared undue: 1961 Bristol South East by-election
• Last by-election result to be declared void: 1892 Cirencester by-election
• First by-election subject to the Corrupt and Illegal Practices Prevention Act 1883: 1883 Limerick City by-election
• First by-election to be held using the secret ballot: 1872 Pontefract by-election