The Bills have agreed to terms with linebacker A.J. Klein on a three-year, $18 million deal that includes $9.7 million fully guaranteed, Adam Caplan of SiriusXM NFL Radio reports.
Bills head coach Sean McDermott coached Klein when McDermott was defensive coordinator with the Panthers.
Klein, 28, spent the past three seasons in New Orleans.
He started 42 of the 43 games he appeared in for the Saints, making 193 tackles, 6.5 sacks, two interceptions, two forced fumbles and nine pass breakups.
Klein played his first four seasons in Carolina after the Panthers made him a fifth-round choice.