Smith's agent, Drew Rosenhaus, told ESPN that the deal includes $31.25 million guaranteed.
As noted by The MMQB's Albert Brees, Smith's new deal is the highest figure for a skill position player in franchise history and tops both the deals by Rob Gronkowski and Randy Moss, among others.
Smith caught a career-high eight touchdowns last season for the Titans, developing one of the most reliable targets for quarterback Ryan Tannehill. He finished the 2020 season with 41 catches for 448 yards, both slight improvements from his 2019 season.
He also played an integral role in Tennessee's pass and run blocking, especially in the wake of the injury to left tackle Taylor Lewan.
The 25-year-old Smith spent the first four seasons of his career with Tennessee after being a third-round pick in the 2017 NFL draft.
In joining the Patriots, he will look to bolster an offense that had just two receivers finish with more than 400 yards receiving. The Patriots' leading tight end last yer was Ryan Izzo, who finished the season with just 13 catches for 199 yards.
The Patriots reportedly re-signed Cam Newton to a one-year deal last week and hold the No. 15 pick in the 2021 NFL draft.
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