Northern Ireland Polling 2026
A fundamentally different political landscape. Sinn Féin leads at 29%, Alliance and DUP tied at 18%. Border poll data shows 47% support for a united Ireland. Northern Ireland politics is structured around identity, the Good Friday Agreement and the legacy of conflict — not the left-right axis of GB politics.
Northern Ireland Party Support Trend
Northern Ireland's party system has undergone significant change since the Good Friday Agreement. The once-dominant Ulster Unionist Party (UUP) and SDLP have declined in favour of the DUP and Sinn Féin respectively, while Alliance has emerged as a significant third force attracting cross-community support. The chart below shows Assembly voting intention trends.
Note: Assembly figures are first preference votes. 2026 is polling data. Minor parties not shown.
A Different Political Landscape
Northern Ireland's politics are structured around constitutional identity — unionist, nationalist, and the growing "other" or cross-community category — rather than the left-right economic axis of Great Britain. The major GB parties (Labour, Conservatives, Reform UK, Liberal Democrats) do not stand in Northern Ireland. Voters choose from NI-specific parties whose primary purpose is to represent their community's constitutional position alongside governing Stormont.
The Good Friday Agreement of 1998 created the power-sharing executive that requires both the largest unionist and largest nationalist party to participate in government together. This consociational arrangement has been the defining feature of NI governance and has periodically broken down when either community's party withdrew. Each breakdown requires negotiation — often involving the Irish and British governments — to restore functioning institutions.
Unionist Bloc
The DUP (18%) and UUP (11%) together command around 29% of the unionist vote. The DUP's decline from its peak of 30%+ reflects fallout from Brexit policy disputes, the Northern Ireland Protocol controversy, and the party's repeated Stormont withdrawals. The Traditional Unionist Voice (TUV) takes a further 5-6%.
Nationalist Bloc
Sinn Féin leads all NI polling at 29% and is by far the largest nationalist party. The SDLP at 10% has been in long-term decline as Sinn Féin absorbed the vast majority of nationalist votes. SF's 2022 Assembly win — the first time a nationalist party topped the poll — was a historic milestone.
Cross-Community Growth
Alliance at 18% is the most significant political story in NI over the past decade. Attracting voters who reject the nationalist-unionist binary, particularly younger and more educated voters, Alliance has grown from a minor party to a major one. It could yet become the second largest NI party in Assembly terms.
Border Poll: United Ireland Support
Polling on a united Ireland has shown a consistent upward trend over the past decade. The most recent surveys show approximately 47% in favour and 43% against, with around 10% undecided. This compares to a situation in 2015 when a clear majority supported remaining part of the UK.
Several factors have shifted opinion. Brexit was the most significant single trigger, particularly because Northern Ireland voted 56% Remain but was taken out of the EU as part of the UK. The changing demographic balance, with Catholics now broadly equal to Protestants in the population and the Catholic community historically more favourably disposed to a united Ireland, is a long-term structural factor. The Alliance surge also reflects a generation of voters for whom constitutional identity is less fixed than it was for their parents.
| Year | United Ireland | Stay in UK | Undecided | Key Context |
|---|---|---|---|---|
| 2015 | ~25% | ~65% | ~10% | Pre-Brexit baseline |
| 2018 | ~35% | ~55% | ~10% | Post-Brexit referendum |
| 2021 | ~42% | ~47% | ~11% | Northern Ireland Protocol era |
| 2023 | ~44% | ~45% | ~11% | Post-Windsor Framework |
| 2026 | 47% | 43% | 10% | Current position — May 2026 |
Note: These figures aggregate multiple polling companies and methodologies. Individual polls show wider variation. Actual border poll outcome would depend on question framing and campaign dynamics.
Stormont Power-Sharing: History of Breakdowns
The Stormont Assembly and Executive have been suspended or effectively non-functional multiple times since the Good Friday Agreement. Each collapse has required intensive political negotiation to restore, and prolonged absences of devolved government have had real consequences for public services, as Westminster civil servants run Northern Ireland departments on autopilot.
| Period | Duration | Cause | Resolution |
|---|---|---|---|
| 2002–2007 | 5 years | IRA spying allegations at Stormont | St Andrews Agreement (2006); DUP-SF power-sharing restored |
| Jan–Jun 2017 | 6 months | RHI heating scandal; Arlene Foster controversy | Fresh elections; restored after further negotiations |
| 2017–2020 | 3 years | Breakdown of DUP-SF relationship following RHI | New Decade, New Approach deal (Jan 2020) |
| 2022–2024 | 2 years | DUP withdrawal over Northern Ireland Protocol/Windsor Framework | Restored February 2024 after updated Windsor Framework deal |
Frequently Asked Questions
Which party leads Northern Ireland polling in 2026?
Sinn Féin leads Northern Ireland Assembly polling at 29% in May 2026. The DUP and Alliance are both at 18%, the UUP at 11% and the SDLP at 10%.
What do border polls show about support for a united Ireland?
The latest polling on a united Ireland shows approximately 47% in favour and 43% against, with around 10% undecided. Support has risen substantially over the past decade, driven partly by Brexit and demographic change. However, these polls do not fully reflect how people would vote in an actual border poll where question framing and campaign dynamics would significantly affect the outcome.
Why has Alliance grown so much in Northern Ireland?
Alliance has grown by attracting voters who identify as neither unionist nor nationalist — a category that has grown significantly among younger and more educated voters. Alliance offers a pro-EU, centrist, cross-community platform that appeals to voters disenchanted with the traditional DUP-Sinn Féin binary. It has grown from around 7% to 18% in Assembly polling over the past decade.
How does Northern Ireland politics differ from Great Britain?
Northern Ireland's politics are structured around constitutional identity — unionist, nationalist, or other — rather than the left-right economic axis of GB. The major GB parties do not stand in Northern Ireland. Stormont operates under a power-sharing executive requiring both communities to participate, based on the Good Friday Agreement. Reform UK, Labour and the Conservatives have no presence in NI elections.
What is the history of Stormont power-sharing breakdowns?
Stormont has collapsed multiple times since 1998. Major collapses include 2002-2007 (IRA spying), 2017 (RHI scandal), 2017-2020 (DUP-SF breakdown) and 2022-2024 (DUP withdrawal over the Northern Ireland Protocol). The most recent restoration came in February 2024 after the DUP agreed to return following updated Windsor Framework arrangements.