Kelly made his debut for the Northern Irish side in the last season and the campaign served as a breakthrough one for him.
The youngster made 29 appearances in all competitions for Coleraine in the past season and was also picked in the squad for the Northern Ireland Under-19s, though he is yet to make his debut.
His displays in the top flight in Northern Ireland attracted interest from a host of Premier League clubs but one side have won out.
The Hammers are close to completing the signing of the youngster who is considered a prospect for the future.
Kelly is currently on international duty with Northern Ireland Under-19s and will complete a medical when he finishes up with the national team.
The 17-year old signed his first professional contract only last October, but now he is set to end up with the Hammers.
If the transfer does indeed go through as has been envisioned, Kelly will be hoping to further his progress with the Hammers while the London club will be looking to have a future star on their hands.
