Dylan Taylor, 17, who now lives in Hampton, Cheshire, made it to the final of the latest series of the Channel 4 programme but was pipped at the post in the conundrum round.
The teenager, who is autistic, scored a total of 974 points over the course of the series, comfortably beating the previous record by nine points.
Dylan moved to the UK from Honduras with his parents and brother following the devastation of Hurricane Mitch in 1998 which killed more than 11,000 people.
Dylan's dad, Simon, originally from Cheshire, ended up in Honduras after years of travelling around the world, including living with Masai tribesmen in Kenya.
In Honduras he met and married local woman, Maritza, and they had two sons, Dylan and Damon, 15.
Of Dylan's Countdown success, Simon, 47, said: "It is a tremendous achievement at such a young age. Dylan has been playing Countdown since he was about six. He used to come home from school and ask to put it on. It just captures his imagination."
He added: "Dylan is autistic. It gives him ability in terms of intelligence but it takes away his confidence and the ability to pick up on social cues. But if he gets interested in something he will excel at it."
Dylan said: "It was great to go on the show, and it was semi-nerve-racking, especially in the final. I have been playing along with the show at home. "People have been saying I really needed to go on, so I did. It was fantastic to get the record, it really has been a dream come true."
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