The Sun reports that the contract - which will see them releasing in the US this summer - is worth £1m.
Sony Masterworks' senior vice president Mark Cavell described Collabro as "tremendously talented".
"I am sure they will win over both the hearts and ears of Americans," he added.
Meanwhile, Collabro member Jamie Lambert said that he has seen a lot of fans "campaigning for US promotion" online.
Collabro interview: 'We've been painted as squeaky clean but we're not!'
"Who knows what this year might bring?" he added. "This time last year we'd only just auditioned for BGT so anything can happen."
Collabro, who will release their second album Act Two in the UK later this year, won Britain's Got Talent in June 2014 and joined Simon Cowell's Syco label just days later.
Their debut album Stars went to number one in the UK charts and was re-released with extra songs in December.
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