James previously wore No. 6 at three Olympic Games and also during his four seasons with the Miami Heat, where he won two titles in 2012 and 2013.
The 36-year-old has donned the famous number 23 for the majority of his career, including during both his stints with the Cleveland Cavaliers, and more recently in his three years with the Los Angeles Lakers.
The surprise move opens the door for fellow Lakers star Anthony Davis to wear No. 23 again.
The giant centre wore No. 23 for the New Orleans Pelicans before selflessly changing to No. 3 when he joined James at the Lakers in 2019.
But Davis reportedly does not have any personal affinity with No. 23 and will stick with No. 3.
James is not the first NBA legend to change numbers mid-career. The late Kobe Bryant wore number eight in his early NBA days before making the switch to number 24.
Michael Jordan made the No. 23 iconic throughout his legendary Chicago Bulls career, leading them to six NBA championships in the 1990s with the two digits on his back.
The move may signal James’ intention to cement a legacy separate to Jordan as his career comes to an end, despite the fact he’s reigniting Space Jam that was made famous by MJ.
The four-time NBA MVP will be looking to draw a line in the sand after a disappointing end to the season.
It was the first time in 15 attempts that a team featuring James has failed to progress past the opening round of the playoffs.
The basketball icon has ruled himself out from competing for Team USA in the upcoming Tokyo Olympics, while he gives his body a rest and focuses on filming Space Jam: A New Legacy, the sequel to the original movie released in 1996 that starred none other than Jordan.
Time will tell if the change to No. 6 is a lucky charm as James strives to add another championship ring to his collection.