County Waterford was a parliamentary constituency in Ireland, represented in the British House of Commons.

It was an original constituency represented in Parliament when the Union of Great Britain and Ireland took effect on 1 January 1801.

In the 1918 election Sinn Féin defeated by 3 to 1 the Nationalist candidate J. J. O'Shee representing the Irish Parliamentary Party.

Sinn Féin contested the general election of 1918 on the platform that instead of taking up any seats they won in the United Kingdom Parliament, they would establish a revolutionary assembly in Dublin.

Power resigned by accepting the office of Steward of the Chiltern Hundreds, causing a by-election.