The Bury by-election, 1902 was a by-election held in England on 10 May 1902 for the House of Commons constituency of Bury in Lancashire.
It was the first by-election gain by the Liberal Party from the ruling Conservatives in the Parliament of 1900–1906 and it can arguably be said to have set in motion the swing to the Liberals from the Tories which brought twenty by-election gains in all over the following months, leading to the Liberals landslide victory in the 1906 general election.
The election was triggered by the resignation of the sitting Conservative Member of Parliament (MP), James Kenyon.
The Conservatives and their Liberal Unionist Party allies already had a candidate in the field, as Kenyon had made known his intention to stand down because of ill-health. They had chosen Harry Lawson,the former Liberal MP.
The Liberals re-selected their candidate from the 1900 general election George Toulmin, a Lancashire newspaper proprietor.
It was reported that at a meeting of socialists at Bury on 28 April 1902 it was agreed to support a socialist candidate at the forthcoming election, if one were nominated. There were splits in the socialist camp however. The Independent Labour Party decided to dissociate itself from the decision of the Social Democratic Federation to bring forward a candidate and chose to support Toulmin. The Labour Representation Committee in Bury held a meeting to decide their position but declined in the end to stand a candidate. The traditional Lib-Lab alignment seemed to holding in Bury with the trade unions in the cotton industry coming out strongly for Toulmin.