Conservatives win Aberdeen South by-election in major Scottish breakthrough

The Scottish Conservatives have broken a long drought in Aberdeen South, taking the seat from the SNP with a majority of 6,050 and turning a former nationalist hold into the party’s biggest Scottish breakthrough in generations. Douglas Lumsden won 14,308 votes on a 38.0% turnout, while the SNP finished second on 8,258, as the same election day also delivered an SNP hold in Arbroath and Broughty Ferry.

The result matters because Aberdeen South had been firmly in SNP hands only two years ago. Stephen Flynn won the seat at the 2024 general election with a majority of 3,758 and a turnout of 59.9%, then resigned from the Commons on 14 May 2026 after being elected to the Scottish Parliament on 7 May. The Scottish Elections (Representation and Reform) Act 2025 bars anyone from serving simultaneously as an MP and an MSP, forcing the by-election that opened the door for the Conservatives.

Lumsden’s campaign leaned heavily on North Sea oil and gas, a pitch aimed squarely at Aberdeen’s economy and its wider energy supply chain. The scale of the win, and the party’s claim that it was its first Scottish by-election gain since Glasgow Pollok in 1967, will be read as more than a local swing. It suggests the Conservatives were able to convert a clear pro-industry argument into votes in a city where energy jobs remain politically salient, even as turnout fell sharply from the 2024 general election.

But the Aberdeen result does not stand alone. On the same day, the SNP held Arbroath and Broughty Ferry, where Lara Bird kept the seat after Stephen Gethins also resigned from Westminster on 14 May for the same dual-mandate reason. That contest had been a narrow SNP hold in 2024, when Gethins won by 859 votes on a 57.9% turnout, and in 2026 Bird defeated Conservative, Reform, Labour and Liberal Democrat challengers as turnout dropped to 31.36% with 23,827 votes cast.

Taken together, the two by-elections point in different directions. Aberdeen South suggests a localized backlash strong enough to lift the Conservatives across the finish line in a seat the SNP had taken comfortably in 2024. Arbroath and Broughty Ferry suggests the SNP can still defend ground where its base is intact, even as participation falls and Westminster competition fragments. The dual outcome is a warning sign for all three main parties: Scottish politics remains fluid, but the battlegrounds are shifting seat by seat, not in one uniform national wave.