The deal is for $24 million, with $11 million in guarantees, according to the NFL Network.
Breeland played college football at Clemson, about three hours from the Panthers' home stadium, and grew up about 3½ hours away in Allendale, South Carolina.
Breeland, 26, has been a starter from the time he joined Washington as a fourth-round pick in 2014. He stood out in a Monday night win at Dallas in his rookie season, successfully defending receiver Dez Bryant in pivotal situations.
Breeland was Washington's best corner in his second season, but the Redskins made a big splash the following offseason by making free agent Josh Norman the league's highest-paid corner. Breeland had an inconsistent 2016, sometimes struggling to keep his emotions in check.
Breeland, who has eight career interceptions, rebounded with a strong season in 2017, starting on the right side. He also averaged 20.8 yards on 10 kickoff returns.
He occasionally played in the slot in his four seasons with Washington.
ESPN's John Keim contributed to this report.