The 19-year-old outside-half was man of the match when Wales under 20s beat England 23-22 at Kingsholm last Friday scoring 18 points. From Pencoed, he was part of the Ospreys U16s set-up before moving to the East Midlands.
He has made a couple of senior appearances for Leicester in Europe this season and has also been on loan with Greene King IPA Championship side Ampthill. “I’m really excited to be playing in Wales with the Scarlets next season,” said Costelow.
“Scarlets are a really good side who’ve been playing some great rugby which I think will suit me. I feel it is the right move for me in how I am going to develop into the player that I want to be and also to fulfil the targets and hopes I want to fulfil in my career.
“I’m extremely grateful for the opportunities that Leicester have provided me. I’ve learnt a huge amount there, especially from a player of the quality of George Ford.
“Hopefully I can now keep developing at the Scarlets.” Costelow will compete with Wales international Rhys Patchell, Angus O’Brien and Dan Jones for the number 10 shirt at Parc Y Scarlets next season.
Scarlets general manager of rugby Jon Daniels said: “We saw on Friday night at Kingsholm, how much of a talent Sam is and we are delighted that he has agreed to join the Scarlets.
“He is one of Welsh rugby’s brightest prospects, highly regarded at Leicester and we are excited to be signing a player of his calibre and looking forward to seeing him develop his game as part of a strong pool of fly-halves at the Scarlets.”
