City boss Stuart Pearce allowed Wright-Phillips to leave with the signing of Paul Dickov putting him 5th in the pecking order up front.
The 21-year-old striker may have made 40 senior appearances for City but started only 3 games, scoring twice.
City accepted an undisclosed fee for BWP which is believed to be in the region of £1m. £250k of the fee came from the Coca-Cola promotion which offered fans of all 72 League and SPL clubs the chance to win money to spend on a new player. The deal also includes a 'substantial' sell-on clause.
"It was a wrench to leave City but it's an exciting challenge," said BWP. "I spoke to my dad (Ian Wright) and he told me all about Southampton, and about George (Burley), and what to expect so I am happy to be here. It's a great club with great facilities."
Saints boss Burley added: "I tried to get him on loan last season but we were turned down. We followed it up this summer and have managed to sign him."
Pearce told the City website: “Commercially, this is a good deal for the club but also for Bradley at this stage in his career."
- City have also bagged £200k from Tyrone Mears' £1m move from Preston to West Ham. City sold the full-back to Preston for £200k in 2002 having made just 1 substitute appearance.
- City have been firmly linked with Reading midfielder Steve Sidwell. Pearce is believed to have made a £2m bid for the 23-year-old, who scored 10 goals as Reading stormed to the Championship title last season.
His contract is up next summer and he has turned down an improved offer but Reading insist they want him to stay and have no intention of selling yet.
- Celtic have rubbished rumours they are lining up a swap deal involving their Bulgarian playmaker Stilian Petrov and Joey Barton.