The 19-year-old has signed a one-year deal at the Banks's Stadium, and manager Dean Smith has revealed that he is impressed with the former Baggies reserve.
The 42-year-old told the Express and Star: "Shane has impressed during his time with us so far.
"He's an up-and-coming talent who we will be able to develop and fits the bill of what we are looking for in terms of attitude, temperament and attributes.
"We see Shane as a player of real potential who will challenge for a starting place."
Lewis has previously represented England's Under-17 side.