The 24-year-old's move is subject to pending confirmation of clearance from the Football League.
"It has been a little bit frantic! Me and the missus jumped in the car and have flown down the M62," Hammill told the Yorkshire club's official website.
"I'm delighted to be signing here. I want to get as much game time as possible and show everyone what I can do."
Since moving to Molineux from Liverpool in January 2011, Hammill has made 23 first-team appearances for Wolves.