The star won the Audience Award, which is voted by the public for their favourite Scot on screen, for his performance in the popular Starz drama.
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Taking to Instagram on Monday morning, the 42-year-old wrote: "Thank you to everyone that voted! So proud of everyone that works on @outlander_starz! Great fun to celebrate with the team.
"Thanks for a great night @baftascotland."
Fans rushed to the comments to congratulate the Jamie Fraser actor, with one person writing: "Congratulations Sam! You deserve it a lot. Thank you very much for bringing to life with so much love, dedication, courage and passion such a beautiful character. If Jamie Fraser is so beloved, iconic, and memorable, it's because the role is played by Sam Heughan."
A second fan commented: "So well deserved Sam! So proud of you. We finally made it! Hope you felt all the love we, the fans, have for you."
Sam won a BAFTA Scotland award on Sunday night
A number of fans also commented on his heartwarming acceptance speech, in which he revealed that the show had employed 2,800 Scottish crew, 650 cast and 5,000 extras over its eight seasons.
One fan wrote: "Sam, you so, so deserve this. Your thank you speech was #purdeandbrilliant!! You show the world what it means to be humble, gracious and thankful all at the same time," while another added: "Congratulations Sam with this award! So well deserved and also congrats to the Outlanderteam. Beautiful, thoughtful speech you gave. Wonderful!"
Sam won the award for his role in Outlander, which he stars in alongside Caitríona Balfe
The good news comes just weeks after Sam opened up about the heartbreaking loss of his father while joining Jackie Bird for an episode of the Love Scotland podcast.
"The loss of my father, actually during the beginning of season one of shooting Outlander, was a big moment in my life," he explained.
"I didn't know him, he left when I was eighteen months old but going to see him in his last moments and visit him and learn a bit more about it definitely had an effect on me, and I think just writing about that has been quite cathartic."
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