Matt, who shot to fame on 2014’s Britain’s Got Talent, broke the news to fans on Tuesday night from the band’s Facebook page.
He said: “She said yes!! And the boys came to Spain to sing during the proposal. So happy!! Matt X.”
Former kitchen salesman Matthew used to be a member of the Carlisle music theatre school StagedRight.
David and Sallie McNeill, who own StagedRight, were among the first to congratulate Matt on his engagement to Sam. They said on Facebook: “Congratulations to StagedRighter Matthew Pagan and his beautiful girlfriend Samantha Neil who got engaged today.”
Sam played the part of a hand maiden and was the first cover narrator at Joseph And The Amazing Technicolour Dreamcoat.
Originally from Jersey, she currently lives in London.
Sam studied musical dance theatre at Bird College of Dance and Theatre Performance and has worked in Harrods as well as being a former lead vocalist on P&O Cruises.
The rest of the band wrote: “On Tuesday evening the Collabro brothers gained a sister-in-law (to be) which is beyond exciting.
“And yesterday morning we woke up to find our new cover (All I Ask by Adele) has had over 20,000 views already.
“We love this family.”
More than 330 fans congratulated the couple on Facebook.
Ann Jones from Etterby Park, Carlisle, said: “Fabulous news. Congratulations to you both.”
Singer Liam Halewood said: “Congrats Matt hope you both have a lifetime of happiness together x see you at Cumbria Pride.”
Matt’s parents, Tony and Linda, live in the St Ann’s area of Carlisle and have supported their son from the outset.
Matt, 23, used to attend Carlisle’s Richard Rose Central Academy.
He regularly returns to the city when he can and has performed at the Sands Centre with his band and in a fundraising gig for the Eden Valley Hospice.
Both Matt and Sam performed together in 2013 at the s Christmas concert. His mum once told the r that Matt’s favourite breakfast was tinned spaghetti and sausages on toast, which she makes him when he comes home.
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