Portarlington (UK Parliament constituency)

Portarlington was a rotten borough and is a former United Kingdom Parliament constituency, in Ireland, returning one MP. It was an original constituency represented in Parliament when the Union of Great Britain and Ireland took effect on 1 January 1801.

Boundaries
This constituency was the Parliamentary borough of Portarlington in Queen's County now called County Laois.

Elections in the 1840s
Dawson-Damer was appointed Comptroller of the Household, requiring a by-election.

Elections in the 1850s
Dunne was appointed Clerk of the Ordnance, requiring a by-election.

Elections in the 1880s
FitzPatrick succeeded to the peerage, becoming Lord Castletown, causing a by-election.