Jackson, 29, will make $26 million in the first two years of the contract and $36 million in the first three. The actual value of the deal is $55,555,555.55, in honor of Bucs quarterback Josh Freeman's jersey No. 5.
Jackson has 272 career catches for 4,754 yards, with 37 touchdowns. He has topped 1,000 receiving yards three times in the past four seasons.
The Bucs entered Tuesday, the first day that teams could sign free agents, with the most salary-cap room in the NFL -- $44.9 million, according to La Canfora. They made a big splash with their first move, adding a dynamic wide receiver to play opposite Mike Williams.