The Social Democratic and Labour Party held its two Westminster seats at the 2024 general election. It did not gain. It did not lose. Colum Eastwood held Foyle with a reduced majority, cut from approximately 17,000 to 4,166 as Sinn Féin pushed hard for the seat. Claire Hanna held Belfast South and Mid Down with a majority of 12,506, the fifth safest seat in Northern Ireland. On 29 August 2024, Eastwood announced his resignation as leader after nine years, the second longest serving leader after John Hume. He said he wanted to focus on the New Ireland Commission and on representing Foyle. Hanna succeeded him unopposed on 5 October 2024, becoming the SDLP's seventh leader. The party once dominated nationalist politics in Northern Ireland. It now sits fifth in the Assembly with eight MLAs, holds two Westminster seats and 39 council seats. Sinn Féin, which overtook it in 2001, holds seven Westminster seats, 28 Assembly seats and 240 council seats across the island. The constitutional nationalist alternative that the SDLP represents has been electorally eclipsed by the abstentionist alternative it was designed to replace.

The 2024 manifesto presented the SDLP as the engaged nationalist party: take seats at Westminster, take the oath, sit on the Labour benches, use Parliament to press for Northern Ireland investment and repeal of the Legacy of the Troubles Act. The two SDLP MPs do all of this. Eastwood described the oath of allegiance to the King as "an empty formula" taken under protest. Hanna sits on the Northern Ireland Affairs select committee and serves as the party's spokesperson for Europe and International Affairs. The voice is consistent. The voice is small. Two MPs against Sinn Féin's seven silent ones. The engaged alternative delivers fewer seats than the principled absence.

At Stormont, when devolution was restored on 3 February 2024, the SDLP designated as official opposition under the Assembly and Executive Reform Act 2016 rather than take a portfolio through the d'Hondt allocation. Matthew O'Toole leads the opposition in the Assembly. The decision was justified as preserving a distinct voice and holding the dominant parties to account. Hanna has used the position to call for Stormont reform, removal of sectarian designation vetoes, and establishment of a New Ireland Commission to build the case for unity by consent. The opposition position produces arguments. The Executive holds the budgets.

On Irish unity the manifesto built the case for a referendum by consent, explicitly distinct from Sinn Féin's 2030 demand for a date. In October 2025 Hanna called on the Irish Government to begin planning for a border poll and establish a dedicated New Ireland ministry. Neither the British nor the Irish Government has accepted the Sinn Féin timetable or the SDLP framework. Both constitutional nationalist arguments have been made and accepted by neither. The unionist bloc vote across multiple parties remains slightly larger than the combined nationalist vote at Westminster. The conditions for a border poll under the Good Friday Agreement, a sustained majority in favour of reunification, have not been demonstrated by any party.

On the economy and welfare the SDLP's positions tracked the Labour framework: end Conservative underfunding, reform the fiscal framework, scrap the two child benefit cap, scrap the bedroom tax. Labour scrapped the cap at the November 2025 Budget. The SDLP's engagement strategy meant delivery came through the party it allies with rather than through SDLP advocacy. The two child cap was won by Labour, not by two SDLP MPs lobbying for it. By manifesto design the party supports rather than opposes the Labour Government. That alignment delivers outcomes. It does not deliver SDLP identity.

On Europe the manifesto positioned the SDLP as the most explicitly pro Windsor Framework party in Northern Ireland, arguing the Framework protected Northern Ireland's dual market access to both the UK and the EU. Labour's May 2025 EU reset moved partially in the SDLP's direction. The position has not been challenged because the government has moved part way toward it.

Hanna's personal trajectory is more interesting than the party's current position suggests. She ousted Emma Little-Pengelly, now the DUP's deputy First Minister, from Belfast South in 2019 with a landslide. She resigned the SDLP whip over proposals for a formal partnership with Fianna Fáil and considered leaving politics entirely. She returned, held her seat, and took the leadership. She is described by party members as having "politics and the SDLP in her DNA" and is the first leader since Hume to hold a Westminster seat with a commanding majority. Whether she can rebuild the party from fifth place in the Assembly to a competitive position at the next Stormont election in 2027 is the practical question.

The structural question is harder. The SDLP offers engagement where Sinn Féin offers abstention. Two MPs who sit, speak and vote against seven who do not. But Sinn Féin holds seven seats to the SDLP's two. It is the largest party in the Assembly, in local government and at Westminster. The nationalist electorate has chosen the abstentionist expression of nationalism over the engaged one by a margin of more than three to one. The SDLP's answer has always been that taking seats and doing the work delivers more for constituents than principled silence. That argument is sound. It has not won the voters. Whether constitutional engagement can compete with abstention's mobilising power, or whether the nationalist electorate has already decided that question, is the verdict that the next Assembly election will deliver.