Smith, 22, from Newton-le-Willows played at Blackbrook ARLFC as a youngster before joining the Saints Development Programme at the age of 11.
He was part of the unbeaten Academy Championship side of 2016 before making his first team debut away at Catalans in 2018 after spending the season on dual-registration at York City Knights and Featherstone Rovers.
Before then he spent a month at Hull KR, gaining valuable first team experience whilst this season he has played five times for Leigh Centurions scoring one try.
Smith has made four Saints senior appearances this season and scored his first Saints try in the win against Hull KR at the Totally Wicked Stadium before scoring his second in the win over Catalans more recently.
Smith spoke exclusively to Saintsrlfc.com and was naturally delighted with his new contract.
“It feels amazing. Being a local lad, growing up in St.Helens and coming watching as a kid it feels great to be able to sign on again and I can now move my career on.
“I would like to thank Eamonn McManus, Mike Rush and Justin Holbrook for having faith in me and trusting me to wear the shirt and do a job for St.Helens.
“It has also been great to train and work alongside the likes of James Roby who has helped me a lot. He has helped me develop my game and I have tried to model my game on the way he plays.
“Watching and coming through the system, there is no better role model than him and hopefully one day I become half the player he has been and have some sort of legacy within the club. That is the ultimate dream.”
Saints Chairman Eamonn McManus said: “It’s fantastic news that Aaron has committed to Saints. Aaron is another one of our successful Academy graduates. He is an example of what can be done with hard work and dedication.
“Aaron is learning from the best in James Roby every day in training and that means he can only improve further with experience and with age.”
Head Coach Justin Holbrook added: “I am delighted Aaron has signed on for another three years.
“Aaron has proven this season he is a Super League player. His performances this season have shown what a bright future he has. He is a great young player to coach and is another product of promoting young players from our academy system. Aaron is learning from the best in James Roby on how the game should be played and what is required off the field to be a Saints player.”
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