Sinn Féin held all seven of its Westminster seats at the 2024 general election, becoming the largest Northern Ireland party in the House of Commons for the first time. Combined with its position as the largest party in the Northern Ireland Assembly since 2022 and the largest in local government since 2023, the result completed an electoral hat trick across every level of representation. Michelle O'Neill was sworn in as First Minister on 3 February 2024, the first Irish nationalist to hold the office. The DUP's Emma Little-Pengelly serves as deputy First Minister. The Stormont Executive has operated continuously through 2025 and 2026. The institutional achievement is real.
The seven MPs do not sit, do not speak and do not vote. They refuse to swear the oath of allegiance to the Crown, which is required to take a seat in the Commons. They forfeit the standard £91,346 annual MP salary. They do, however, claim parliamentary expenses for staffing, office costs and travel under a 1933 Commons resolution that permits allowances for non sitting members. The Windsor Framework, the Illegal Migration Act, the Troubles legacy legislation, welfare reform and Westminster budget decisions affecting Northern Ireland's block grant are all decided without Sinn Féin participation. A party pursuing Irish unity has chosen to absent itself from the chamber that decides Northern Ireland policy. Seven seats. Zero votes. Zero contributions recorded in Hansard. The principled case for abstention has been made for decades. The practical cost is that every reserved matter affecting Northern Ireland is decided by parties that showed up.
The constitutional progress the institutional success was supposed to deliver has not arrived. The 2024 manifesto demanded the British and Irish Governments set a date for a referendum on Irish unity by 2030, supported by a citizens' assembly and a joint Oireachtas committee to plan the transition. Mary Lou McDonald has continued to make the demand, accusing Taoiseach Micheál Martin of being the "biggest barrier" to unity. The British Government's position remains that a referendum will be called only when conditions suggest a majority would vote for reunification. Sinn Féin has published no evidence that those conditions exist. Polling on the question has fluctuated but has not shown a sustained nationalist majority. The unionist bloc vote across multiple parties remains slightly larger than the combined nationalist vote at Westminster. The 2030 demand has not become a 2030 plan.
The Republic of Ireland general election in late 2024 made the constitutional position harder, not easier. Sinn Féin won 39 seats in the 174 seat Dáil, finishing second but returning to opposition. Its vote share fell 5.5 percentage points from the 24.5 percent that had made it the largest party by first preference votes in 2020. It was the first time Sinn Féin's vote share had declined in 35 years and the largest fall of any party. The result was described as a significant setback that would prompt "root and branch review of the party's positioning, tactics, organisation and personnel." A Fianna Fáil and Fine Gael dominated coalition was formed without Sinn Féin. The unity momentum the manifesto assumed, a party dominant on both sides of the border pressing both governments toward a referendum, now runs in one direction only. Sinn Féin leads in Northern Ireland. In the Republic it is in opposition, weakened, and unable to set the terms of the constitutional conversation.
On the NHS the manifesto committed to additional capital investment and reform at Stormont. Health is a devolved responsibility. Waiting times, A&E performance and recruitment across the Northern Irish health system have been the dominant questions through 2025 and 2026. Sinn Féin controls the file through Stormont and cannot blame Westminster for the outcomes.
On welfare the manifesto's central demand was Westminster scrapping the two child benefit cap. Labour scrapped the cap at the November 2025 Budget. The defining welfare commitment the party took into the election has been delivered by the party that governs from the chamber Sinn Féin refuses to enter.
This is not a party that broke its manifesto. Sinn Féin delivered the institutional commitment: O'Neill is First Minister, the Executive operates, abstention continues as promised. The party recruited Pat Cullen, the former head of the Royal College of Nursing, as its candidate in Fermanagh and South Tyrone, a move described as a political coup that demonstrated the party's increasing relevance for trade unionism across the island.
But the constitutional progress the manifesto presumed has not happened. The 2030 referendum has not been promised by either government. The Republic election did not deliver the all island momentum required. The party dominant in Northern Ireland is unable to deliver the unity that justified its founding purpose. Seven seats held, all seven silent, and a unity strategy that depends on two governments neither of which has agreed to hold the vote. Whether Stormont success can carry constitutional ambition when the party has chosen to absent itself from the only parliament with the legal power to call a referendum is the question Sinn Féin has not yet answered.