The 2026 Holyrood Election was the “least proportional” Scotland has ever had according to a professor at the University of Edinburgh.

Speaking on BBC Scotland’s Sunday Show, Edinburgh University Professor of political science Ailsa Henderson explained that proportionality “is the way in which the percentage of seats won relates to the percentage of votes earned”.

Prof Henderson said this year’s turnout could be the least proportional Scotland has seen because of “split ticket voting” where voters have voted for different parties on the constituency and regional list ballots.

Scottish Parliament elections
First Minister and SNP leader John Swinney with some of the newly elected SNP MSPs after the Holyrood 2026 election (Jane Barlow/PA)

She continued: “Our results are always more proportional than UK elections because of the electoral system we use, but this is the least proportional one and partly that is to do with split ticket voting – so people voting for different parties on the constituency and on the list.

“The ability of the list to correct for disproportionality in the constituencies only works if people vote for the same party on the constituency and the list.

“And we know that… whether because people genuinely prefer a party that only stands on the list or because they’re trying to game the system in some strategic way, split ticket voting was at an all time high, more than half of people voted for a different party and that figure was about 30% in 2021.”

The results of the 2026 Scottish Parliament election revealed the SNP had 58 MSPs – seven short of a majority and down from the 64 the party won in 2021.

Reform UK, who only had one MSP before the election, were tied with Labour for second place, with 17 MSPs each – though this was down from the 22 seats Anas Sarwar’s party won five years ago.

It was, in fact, the most volatile election we've ever had

Ailsa Henderson, Edinburgh University Professor

The Scottish Greens, meanwhile, returned 15 MSPs, a record high.

The Tories returned 12 MSPs to the Scottish Parliament – down from 31 at the last election and their worst ever result at Holyrood – with the Scottish Liberal Democrats seeing their total increase to 10.

Prof Henderson also said that this year’s election was “twice as volatile” as the 2011 election.

She said: “We wouldn’t expect it to be, because it was an election that returned a sitting government, but it was, in fact, the most volatile election we’ve ever had.

“Twice as volatile as the 2011 election, which saw the SNP deliver the Scottish Parliament’s only majority.”