This past season was Amos' best in the pros, as he secured a pair of interception and made a career-high 73 tackles for the Bears while starting in 16 games.
Smith has played outside linebacker and defensive end for Baltimore since entering the National Football League as a fourth-round selection in the 2015 draft.
"We want to thank Nick for his contributions to the Green Bay Packers and the community over the last seven seasons", Packers general manager Brian Gutekunst said in a statement.
He has twice finished with eight sacks in a season - in his rookie year in 2015 and again in 2017. Also, he's slated to earn $34.5 million in the first two years of the deal.
Smith struggled a bit last season, accruing only four sacks on the season.
"Amos is an excellent safety who's been great for Chicago over the past couple of seasons", The Ringer's Robert Mays writes.
The Packers will have a new full-time head coach in 2019 for the first time in over a decade. And that's what drops his grade just a little. And the player gets a good chunk of guaranteed money, which is the goal for players in every contract negotiation. The defense certainly deserves its share of the blame.