# 2026 Aberdeen South by-election
The 2026 Aberdeen South by-election was a UK parliamentary by-election held on Thursday 18 June 2026 for the constituency of Aberdeen South, won by Douglas Lumsden of the Scottish Conservative and Unionist Party with 49.5% of the vote, a Conservative gain from the [Scottish National Party](https://www.edgepedia.org/scottish-national-party) (SNP).[1](https://www.parliament.uk/business/news/2026/june-2026/new-mps-elected-at-june-by-elections/) • [2](https://members.parliament.uk/constituency/4450/election/557) The seat fell vacant when the sitting MP, Stephen Flynn of the SNP, resigned on 14 May 2026.[3](https://www.parliament.uk/about/how/elections-and-voting/by-elections/by-elections-since-the-2024-general-election/)
| Key fact | Detail |
|---|---|
| Date | Thursday 18 June 2026[1](https://www.parliament.uk/business/news/2026/june-2026/new-mps-elected-at-june-by-elections/) |
| Cause | Resignation of Stephen Flynn (SNP), 14 May 2026[3](https://www.parliament.uk/about/how/elections-and-voting/by-elections/by-elections-since-the-2024-general-election/) |
| Result | Conservative gain from SNP; Douglas Lumsden 14,308 votes (49.5%)[2](https://members.parliament.uk/constituency/4450/election/557) |
| Majority | 6,050 over SNP candidate Richard Gordon Thomson[2](https://members.parliament.uk/constituency/4450/election/557) |
| Turnout | 38% of an electorate of 76,033[2](https://members.parliament.uk/constituency/4450/election/557) |
| Candidates | 7[2](https://members.parliament.uk/constituency/4450/election/557) |
| Previous contest | At the 2024 general election the SNP held the seat with 32.8% against 24.7% for Labour, majority 3,758, turnout 59.9%[4](https://www.pollcheck.co.uk/constituencies/aberdeen_south/) |
## Why the by-election was called
[Stephen Flynn](https://www.edgepedia.org/stephen-flynn), the SNP's Westminster leader, was elected to the [Scottish Parliament](https://www.edgepedia.org/scottish-parliament) on 7 May 2026. The Scottish Elections (Representation and Reform) Act 2025 bars a dual Holyrood and [Westminster](https://www.edgepedia.org/westminster) mandate, so he resigned the Commons seat on 14 May 2026, triggering the by-election.[5](https://ukelections.co.uk/by-elections/aberdeen-south/) A parallel situation produced the Arbroath and Broughty Ferry by-election on the same day, when Stephen Gethins also moved to the Scottish Parliament; the Institute for Government describes both Scottish contests as triggered after the two former SNP MPs were elected in May's devolved elections.[6](https://www.instituteforgovernment.org.uk/explainer/by-elections-since-2024-general-election) A third by-election that day, in Makerfield, followed the resignation of Josh Simons.[1](https://www.parliament.uk/business/news/2026/june-2026/new-mps-elected-at-june-by-elections/)
## Result
Lumsden won 14,308 votes, 49.5% of those cast, a gain of 25.1 percentage points on the Conservatives' 2024 share, taking the seat from the SNP with a majority of 6,050.[2](https://members.parliament.uk/constituency/4450/election/557) The SNP candidate, Richard Gordon Thomson, a former MP and council leader, took 8,258 votes (28.6%), down 4.2 points from the party's 2024 result.[2](https://members.parliament.uk/constituency/4450/election/557)
The full result:[2](https://members.parliament.uk/constituency/4450/election/557)
| Candidate | Party | Votes | Share | Change from 2024 |
|---|---|---|---|---|
| Douglas Lumsden | Conservative | 14,308 | 49.5% | +25.1 |
| Richard Gordon Thomson | SNP | 8,258 | 28.6% | −4.2 |
| Jo Hart | Reform UK | 2,478 | 8.6% | +1.7 |
| Nurul Hoque Ali | Labour | 1,550 | 5.4% | −19.2 |
| Mel Sullivan | Liberal Democrat | 1,270 | 4.4% | −1.9 |
| Jorg Shelton-Eckstein | Scottish Green Party | 974 | 3.4% | −0.1 |
| David Ballantine | Alliance for Democracy and Freedom | 59 | 0.2% | +0.2 |
Turnout was 38%, against 59.9% at the 2024 general election in the same seat.[2](https://members.parliament.uk/constituency/4450/election/557) • [4](https://www.pollcheck.co.uk/constituencies/aberdeen_south/) The Commons Library notes that the constituency's boundaries changed following a review in 2023, so its comparable election history begins with the 4 July 2024 general election.[7](https://members.parliament.uk/constituency/4450/election-history)
## The campaign
**Oil and gas dominated.** The Guardian's pre-polling-day report described the contest as a straight fight between the SNP and the Conservatives over the future of [North Sea oil](https://www.edgepedia.org/north-sea-oil) and gas, in a constituency that includes the port of Aberdeen and its rig-support industry.[8](https://www.theguardian.com/politics/2026/jun/17/oil-gas-industry-aberdeen-south-byelection-snp-tories-energy-policy) The Conservatives campaigned on maximizing oil and gas extraction to protect jobs, revenues and energy security; Conservative leader [Kemi Badenoch](https://www.edgepedia.org/kemi-badenoch), on her third visit to the seat two days before the poll, said voting Tory would give the sector a "kiss of life".[8](https://www.theguardian.com/politics/2026/jun/17/oil-gas-industry-aberdeen-south-byelection-snp-tories-energy-policy)
The economic background weighed on the contest. The energy sector was shedding about 1,000 jobs a month; universal credit take-up in the constituency had risen 30% since April 2022, with almost 10,000 local claimants and 8,800 families needing state benefits.[8](https://www.theguardian.com/politics/2026/jun/17/oil-gas-industry-aberdeen-south-byelection-snp-tories-energy-policy) The SNP argued the Conservatives were "no friends to the oil and gas industry", pointing to the energy profits levy introduced by the Conservatives and to about 70,000 [North Sea](https://www.edgepedia.org/north-sea) jobs lost under the previous UK government; Lumsden replied that the SNP had voted for that levy and that "there is no windfall to tax".[8](https://www.theguardian.com/politics/2026/jun/17/oil-gas-industry-aberdeen-south-byelection-snp-tories-energy-policy)
Lumsden, who had stood for the seat in 2019 and come second behind the SNP on 36% of the vote, predicted tactical voting from former Reform and Labour supporters, and the Conservatives focused on voters hostile to the SNP.[8](https://www.theguardian.com/politics/2026/jun/17/oil-gas-industry-aberdeen-south-byelection-snp-tories-energy-policy) No constituency polling was published for the by-election.[5](https://ukelections.co.uk/by-elections/aberdeen-south/) The ukelections.co.uk pre-election call, made on a poll-of-polls basis, had been for the SNP, and the site records the result as going the other way, with a swing of +20.9 percentage points to the Conservatives.[9](https://ukelections.co.uk/by-elections/)
## Significance
The result was one of the six by-elections held since the 2024 general election, and the only one of the three 18 June contests that changed hands: Labour held Makerfield, the SNP held Arbroath and Broughty Ferry, and the Conservatives gained Aberdeen South.[6](https://www.instituteforgovernment.org.uk/explainer/by-elections-since-2024-general-election) • [3](https://www.parliament.uk/about/how/elections-and-voting/by-elections/by-elections-since-the-2024-general-election/) It returned the seat to the Conservatives, whose win came a parliament after the SNP had taken the constituency from Labour in 2024.[4](https://www.pollcheck.co.uk/constituencies/aberdeen_south/) Lumsden remains the sitting MP, with PollCheck's current projection putting the Conservatives on 28.4% and the SNP on 28.1% in the constituency, a margin of 0.3 points.[4](https://www.pollcheck.co.uk/constituencies/aberdeen_south/)
## References
1. [New MPs elected at June by-elections, UK Parliament, 19 June 2026](https://www.parliament.uk/business/news/2026/june-2026/new-mps-elected-at-june-by-elections/)
2. [Election result for Aberdeen South, 18 June 2026 by-election, UK Parliament](https://members.parliament.uk/constituency/4450/election/557)
3. [By-elections since the 2024 general election, UK Parliament](https://www.parliament.uk/about/how/elections-and-voting/by-elections/by-elections-since-the-2024-general-election/)
4. [Aberdeen South constituency profile, PollCheck](https://www.pollcheck.co.uk/constituencies/aberdeen_south/)
5. [Aberdeen South by-election 2026 result, UK Elections](https://ukelections.co.uk/by-elections/aberdeen-south/)
6. [By-elections since the 2024 general election, Institute for Government](https://www.instituteforgovernment.org.uk/explainer/by-elections-since-2024-general-election)
7. [Election history for Aberdeen South, UK Parliament](https://members.parliament.uk/constituency/4450/election-history)
8. ["No friends to the oil and gas industry": Aberdeen South, the byelection where one topic dominates, The Guardian, 17 June 2026](https://www.theguardian.com/politics/2026/jun/17/oil-gas-industry-aberdeen-south-byelection-snp-tories-energy-policy)
9. [UK parliamentary by-elections: results, forecasts and what's next, UK Elections](https://ukelections.co.uk/by-elections/)
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*Topic: Encyclopedia › Society and history › Politics and government › Elections and representation › Elections and referendums › United Kingdom election events › UK parliamentary by-elections › UK parliamentary by-elections 2019–present*
*Initially written Sep 17, 2026 · Reviewed: Oct 25, 2026 · Edited: Oct 15, 2026; Oct 25, 2026 · Last review: Oct 25, 2026*
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License: Edgepedia Community License 1.0, https://www.edgepedia.org/edgepedia/license