Mahoney, who played 14 times in the Championship last season, has put pen to paper on a four-year contract with the Cherries and will initially join the club's Under-23 squad.
His young age dictates that a compensation fee will still have to be paid to Blackburn, despite it technically being a 'free' transfer, and Bournemouth have confirmed that talks over the size of the fee are currently ongoing. If no agreement is reached, a tribunal will be required.
"I think I'm ready to step up and challenge myself. I'm a young, hungry player, who wants to attack and get past my man," an eager Mahoney told AFCB.co.uk.
"I like to get fans off their seat and I'm trying to make my way in the game. Working with Eddie Howe and his coaching staff will be a dream come true, so to be able to do that day in, day out will get the best out of me."
Howe himself commented, "I'm very pleased to welcome Connor to the football club. He is a player we have very high hopes for. He has a lot of potential and hopefully it will be a really good deal for both him and us.
"He put in a number of eye-catching appearances for Blackburn in a short space of time at the end of last season, so we quickly evaluated the situation and made a move for him. There's a lot more to come from him and we will look to develop his talent."