Bournemouth manager Eddie Howe has vowed to give his promotion heroes the chance to shine in the Premier League.
Wolves boss Kenny Jackett fears he will lose key winger Bakary Sako after his side missed out on a place in the play-offs.
The club say they have paid a "substantial" undisclosed fee for the 27-year-old, who has been on loan with the Millers since October and scored four goals in 16 appearances.
Frecklington has put pen to paper on a two-and-a-half year deal after the two clubs agreed a fee earlier this week.
The transfer is subject to Football League and FA ratification.