Pierre-Louis, 28, can earn up to $3.45 million with incentives, the report said. He played in 66 percent of the Bears' special teams snaps in 2019.
Pierre-Louis was selected by the Seahawks in the fourth round of the 2014 draft. He has played with four teams over six NFL seasons.
The Bears have a depth void to fill at inside linebacker after losing Nick Kwiatkoski and now Pierre-Louis in free agency. They did retain Danny Trevathan on a three-year deal to start alongside Roquan Smith.