She failed to hold on to the Dunbartonshire East constituency, suffering a humiliating defeat just five months after being elected as leader of her party.
Ms Swinson won 19,523 votes to the SNP’s 19,672, losing by a margin of just 149. At the time of writing the Liberal Democrats actually gained votes in every seat in Scotland declared so far – other than their leader’s own.
She won the constituency by 5,339 votes in 2017 but it was a top target for the SNP this time around.
Even if she had held on, Ms Swinson was set to face calls to resign as party leader after a disappointing night for the Liberal Democrats, with the party forecast to win just 15 seats.
Speaking after the result was announced, Ms Swinson said: “For millions of people in our country, these results will bring dread and dismay and people are looking for hope.
“I still believe that we as a country can be warm and generous, inclusive and open, and that by working together with our nearest neighbours we can achieve so much more.
“Liberal Democrats will continue to stand up for these values that guide our liberal movement: openness, fairness, inclusivity. We will stand up for hope.”
She promised to make a further announcement about her future later on Friday.
In a statement released early on Friday morning, the party said Ed Davey and Baroness Sal Brinton will become joint acting-leaders of the Liberal Democrats, with a leadership election set to take place in 2020.
"I want to thank Jo Swinson for her honest and fearless leadership of the Liberal Democrats," Baroness Brinton said.
"In the weeks ahead we will elect a new leader and our party will continue to be the rallying point for anyone who believes in a country where everyone has the chance to get on in life."
Earlier in the night, the Liberal Democrats’ House of Lords leader, Lord Newby, insisted that the general election result was not a disaster for his party.
He told Sky News: “Our vote share will have gone up, the number of seats will have gone up. Our view at the moment is that the position in Scotland for us is rather better than the poll suggests.
“Like everybody, we want a lot more votes and a lot more seats. We’re going to get some more votes and some more seats, at a time when the other party that’s been arguing on a Remain platform has completely collapsed. We have not completely collapsed – we’ve moved forward not as much as we’d wanted, by a very long way.”
The exit poll suggested that the SNP is on course to increase its number of seats from 35 to 55.
Nicola Sturgeon, the SNP leader, tweeted: “Exit poll suggests good night for the SNP – but it is just an exit poll and there are many marginals, so let’s just wait and see. What it indicates UK wide though is grim.”
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