The Dolphins, who were expected to release the tailback, announced they acquired a conditional seventh-round pick in the 2021 NFL Draft in exchange for Ballage.
Ballage will be reunited with Jets head coach Adam Gase, who was the Dolphins' coach from 2016-18. Gase played a part in Miami's decision to select the 24-year-old running back in the fourth round of the 2018 draft out of Arizona State.
Ballage becomes the second ex-Dolphins running back to join Gase and the Jets. Veteran tailback Frank Gore, who helped mentor Ballage as a rookie, signed a one-year deal with the Jets in May.
Ballage was the Dolphins' starting running back in Week 1 last season, but he struggled and eventually lost his job. Miami acquired Jordan Howard and Matt Breida this past off-season.
In his first two seasons, Ballage recorded 326 rushing yards and four touchdowns on 110 carries. He added 23 receptions for 119 yards on 35 targets.