Butler's deal is worth upward of $61 million over five years with more than $30 million guaranteed, a source told Ian Rapoport of NFL Network. His average annual salary of $12.2 million would place him ninth among cornerbacks, according to Spotrac.
The 28-year-old burst onto the scene in 2014, making the famous Super Bowl XLIX goal-line play to help the Patriots beat the Seattle Seahawks.
However, the Patriots seemed reticent to hand Butler a big-money deal. They paid Stephon Gilmore instead during last year's offseason, and Butler's exit was likely sealed when Bill Belichick decided to bench him for the entirety of the Super Bowl loss to the Philadelphia Eagles.
Butler joins a Titans defense in dire need of a stabilizing force in the secondary. Tennessee finished 25th in the league in passing yards allowed per game.