The 17-year-old Ghanaian has signed a two-year deal having impressed Blues boss Lee Clark hugely since arriving at the club from non-league Woodford United.
Born in Kumasi, the versatile forward has featured for both Blues’ U18s and U21s sides this season and was handed a first-team squad number back in February.
Clark, who has previously described Arthur as ‘a pocket battleship’, has regularly highlighted the exciting attacking talent the teenager possesses and is now delighted that he’s committed his future to Blues.
“It’s a real coup to have Koby tied down to a professional contract and if he keeps progressing then we may well see him make his first-team debut before the end of the season,” said Clark.
“I have been hugely impressed with Koby and he has now become involved with the first-team group on a daily basis. He has a big future ahead of him and he fits the bills in terms of my philosophy of building a young, hungry and talented squad here at Birmingham City.”
Arthur’s first pro deal is a real feather in the cap for the Blues Academy recruitment process after the youngster was spotted playing on the non-league pitches of Northamptonshire.
Blues’ Academy Manager, Kristjaan Speakman, added: “It's testament to the recruitment department. Through a network of contacts and scouts we have managed to identify and recruit the player in a competitive arena.
“Furthermore the staff have been fantastic in making Koby feel welcome, going out their way to help ease the transition to life at the academy. I'm sure that this combined with the manager’s philosophy is why he has chosen to commit himself to Birmingham City.”