Julio Rodriguez is set to earn a fortune.

The 21-year-old phenom has agreed to a long-term extension with the Mariners, The Post’s Jon Heyman confirmed on Friday.

MLB Media’s Jesse Sanchez first reported the deal as being worth a minimum of over $200 million and up to $450 million. ESPN’s Jeff Passan added that the deal is for up to 14 years, though both the player and team hold options somewhere in the middle.

Rodriguez is batting .269 with 20 homers, 64 RBIs, a .799 OPS and 20 steals in his rookie season for the Mariners.

He is only the fourth rookie ever to put together a 20-20 season, joining Marty Cordova from the 1995 Twins, Ellis Burks from the 1985 Red Sox and Mitchell Page from the 1977 A’s.

The Mariners are 68-57 and would be in position for their first postseason berth since 2001 if the regular season ended today.