"Kurt brings Origin experience and has played plenty of games in the NRL. He adds a lot of depth to the roster,'' Wests Tigers coach Benji Marshall said.
Marshall also pointed to Mann's leadership, uncompromising style, versatility and competitiveness.
The Tigers have signed the 33-year-old utility on a one-year deal for 2027.
Mann has played 235 NRL games since making his first-grade debut for the Melbourne Storm in 2014.
He played three Origin games for Queensland in 2025.
His previous clubs include the Melbourne Storm, St George-Illawarra Dragons, Newcastle Knights and Canterbury-Bankstown Bulldogs.
"I'm really looking forward to joining the Wests Tigers, connecting with the playing group and coaches,'' Mann said.
"I can't wait to get stuck into some hard work and giving 2027 a red-hot shake."