Stoke complete Bardsley deal
Bardsley joined Sunderland from home-town club Manchester United in a £2million switch in January 2008 after loan moves to Royal Antwerp, Burnley, Rangers, Aston Villa and Sheffield United and established himself as first-choice right-back.
However, he fell out of favour with former boss Paolo Di Canio and seemed destined to leave the club last summer, when only a foot injury scuppered a proposed move to Fulham.
Di Canio took a dim view of the player being pictured lying on the floor of a casino covered in £50 notes, and was even less impressed with an ill-advised tweet after the club's 1-0 home defeat by Fulham on the opening day of the Barclays Premier League season.
However, he was handed a clean slate by new manager Gus Poyet after he replaced the controversial Italian in October last year, and rehabilitated himself to such an extent that he started the Capital One Cup final against Manchester City in March.
Manager Mark Hughes believes Bardsley will be a valuable addition to his squad.
He told stokecityfc.com: "I'm really pleased to bring Phil in to the club.
"He's a player of great Premier League experience who I think will bring added quality to the squad.
"He has plenty of qualities that will improve us and help move the Football Club forward to where we want to be.
"Phil was genuinely excited to join and I'm delighted to bring him in as his personality and desire will shine in the dressing room."