The 1878 Down by-election was fought on 17 May 1878. The byelection was fought due to the death of the incumbent Liberal MP, James Sharman Crawford. It was won by the Conservative candidate Viscount Castlereagh. [1]
The 1878 Londonderry County by-election was fought on 18 December 1878. The byelection was fought due to the death of the incumbent Liberal MP, Richard Smyth. It was won by the Liberal candidate Sir Thomas McClure.
The 1878 New Ross by-election was fought on 17 December 1878. The byelection was fought due to the death of the incumbent Home Rule MP, John Dunbar. It was won by the Conservative candidate Charles George Tottenham.
The 1878 Bristol by-election was fought on 14 December 1878. The byelection was fought due to the resignation of the incumbent Liberal MP, Kirkman Hodgson. It was won by the Liberal candidate Lewis Fry.
The 1878 Peterborough by-election was fought on 29 October 1878. The byelection was fought due to the death of the incumbent Liberal MP, George Hammond Whalley.
The 1878 Argyllshire by-election was fought on 27 August 1878. The byelection was fought due to the resignation of the incumbent Liberal Member of Parliament, the Marquess of Lorne to become Governor General of Canada. It was retained by Lorne's brother the Liberal candidate Lord Colin Campbell.
The 1878 Haddington Burghs by-election was fought on 3 August 1878. The byelection was fought due to the resignation of the incumbent Liberal MP, Sir Henry Ferguson Davie. It was won by the Liberal candidate Lord William Hay.
The 1878 Flint Boroughs by-election was fought on 5 July 1878. The byelection was fought due to the death of the incumbent Liberal MP, Peter Ellis Eyton. It was won by the Liberal candidate John Roberts.
The 1878 Southampton by-election was fought on 14 June 1878. The byelection was fought due to the death of the incumbent Conservative MP, Russell Gurney. It was won by the Conservative candidate Alfred Giles.
The 1878 Reading by-election was fought on 17 May 1878. The byelection was fought due to the death of the incumbent Liberal MP, Sir Francis Goldsmid. It was won by the Liberal candidate George Palmer.
The 1878 West Kent by-election was fought on 15 May 1878. The by-election was fought due to the resignation in order to contest Oxford University of the incumbent Conservative MP, John Gilbert Talbot. It was won by the Conservative candidate Viscount Lewisham.
The 1878 Oxford University by-election was fought on 13–17 May 1878. The byelection was fought due to the elevation to the peerage of the incumbent Conservative MP, Gathorne Hardy. It was won by the Conservative candidate John Gilbert Talbot.
The 1878 North Staffordshire by-election was fought on 24 April 1878. The byelection was fought due to the elevation to the peerage of the incumbent Conservative MP, Charles Adderley. It was won by the Conservative candidate Robert William Hanbury.
The 1878 Mid Somerset by-election was fought on 19 March 1878. The byelection was fought due to the resignation of the incumbent Conservative MP, Ralph Neville-Grenville. It was won by the Conservative candidate William Gore-Langton.
The 1878 Hereford by-election was fought on 14 March 1878. The byelection was fought due to the resignation of the incumbent Conservative MP, Evan Pateshall. It was won by the Conservative candidate George Arbuthnot.
The 1878 Canterbury by-election was fought on 2 March 1878. The byelection was fought due to the resignation of the incumbent Conservative MP, Henry Munro-Butler-Johnstone. It was won by the Conservative candidate Alfred Gathorne-Hardy, who was unopposed.
The 1878 Oxfordshire by-election was fought on 5 February 1878. The byelection was fought due to the resignation of the incumbent Conservative MP, Joseph Warner Henley. It was won by the Conservative candidate Edward William Harcourt.
The 1878 Perthshire by-election was fought on 2 February 1878. The byelection was fought due to the death of the incumbent Conservative MP, Sir William Stirling-Maxwell. It was won by the Conservative candidate Henry Home-Drummond-Moray.
The 1878 Marlborough by-election was fought on 31 January 1878. The byelection was fought due to the succession to a peerage of the incumbent Liberal MP, Lord Ernest Brudenell-Bruce. It was won by the Liberal candidate Lord Charles Brudenell-Bruce.
The 1878 Perth by-election was fought on 29 January 1878. The byelection was fought due to the succession to a peerage of the incumbent Liberal MP, Arthur Kinnaird. It was won by the Liberal candidate Charles Stuart Parker.
The 1878 Leith Burghs by-election was fought on 29 January 1878. The byelection was fought due to the resignation of the incumbent Liberal MP, Donald Robert Macgregor. It was won by the Liberal candidate Andrew Grant.