Sinn Féin
Party Ideology & History
The original Sinn Féin was founded in 1905 by Arthur Griffith. Today's party dates to a January 1970 split over whether to abandon abstentionism, when the minority faction under Ruairí Ó Brádaigh broke away as 'Provisional' Sinn Féin, closely associated with the Provisional IRA through the Troubles. Gerry Adams led the party for 35 years from 1983, steering it through the peace process and the 1998 Good Friday Agreement towards mainstream electoral politics, before handing over to Mary Lou McDonald in 2018.
Sinn Féin ("We Ourselves") is Ireland's oldest political party, founded in 1905 by Arthur Griffith. It campaigns for Irish unity and takes left-wing economic positions on housing, health, and cost of living. Led by Mary Lou McDonald since 2018, Sinn Féin surged to become the largest party by first-preference votes in the 2020 election and remains the largest opposition party. In 2024 it won 39 seats and 19.01% of the vote. The party also operates in Northern Ireland and is the largest party in the Northern Ireland Assembly. Sinn Féin seeks a citizens' assembly on Irish unity and a border poll.
Party Leadership
- Gerry Adams 1983–2018
- Ruairí Ó Brádaigh 1970–1983
Sinn Féin Since 2007
First-preference national vote share across the last five general elections, plus today's polling average (dashed outline — a polling average, not an election result) — the same long-run record this site's seat projection model uses to calibrate how efficiently Sinn Féin's vote converts into seats. Hover a bar for seats won.
Vote-transfer environment: today's poll mix is more favourable for Sinn Féin's PR-STV transfers than the 2024 result was (+0.8% on its baseline seat-conversion rate), based on how the parties that tend to transfer well to it are currently polling relative to 2024. .