Louth is a parliamentary constituency represented in Dáil Éireann, the lower house of the Irish parliament or Oireachtas. The constituency elects five deputies (Teachtaí Dála, commonly known as TDs) on the system of proportional representation by means of the single transferable vote (PR-STV). It covers the entirety of County Louth and a small area of County Meath.
Boundaries
The constituency was created by the Electoral Act 1923, and first used at the 1923 general election.
|Created from Louth–Meath
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|1961–1977
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|County Louth, except the part in the constituency of Monaghan.
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|- valign="top"
|1977–1981
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|County Louth;<br/>
and in County Monaghan, the district electoral divisions of Drumboory, Inishkeen, Kiltybegs, in the former Rural District of Carrickmacross.
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|- valign="top"
|1981–2011
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|County Louth.
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|- valign="top"
|2011–2024
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|County Louth;<br/>
and in County Meath, the electoral divisions of Julianstown, St. Mary's (part), in the former Rural District of Meath.
|Transfer of territory from Meath East
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|2024–
|align="center"|5
|County Louth;<br/>
and in County Meath, the electoral division of St. Mary's (part), in the former Rural District of Meath.
|Transfer of Julianstown to Meath East
|}
TDs
Electoral division
Louth population as per electoral division, for the Dáil constituency of Louth. This population count includes those within the county of Louth, as well as the electoral divisions of Julianstown, and St. Mary's (part) in the county of Meath, as per the Electoral (Amendment) (Dáil Constituencies) Act 2017.
|numcounts = 20
2020 general election
2016 general election
1992 general election
1989 general election
1987 general election
November 1982 general election
February 1982 general election
1981 general election
Pádraig Faulkner was Ceann Comhairle at the dissolution of the 21st Dáil and therefore deemed to be returned automatically. The constituency was treated as a three-seater for the purposes of calculating the quota.