Booker's deal, agreed to early Friday, begins in 2024-25 and brings his total contract value to six years and $295 million.
Booker, 25, has become the face of the Suns franchise since being drafted 13th overall by Phoenix in the summer of 2015, including leading the Suns -- alongside future Hall of Famer Chris Paul -- to the NBA finals in 2021.
Now, he is officially tethered to Phoenix through the 2027-28 season after agreeing to this four-year extension, which won't even begin until after his current contract expires following the 2023-24 season.
Booker averaged 26.8 points, 5 rebounds and 4.8 assists this past season for Phoenix, making his third straight All-Star appearance and finishing fourth in the league's Most Valuable Player award voting. He was also named to the All-NBA first team as he played for a Suns team that finished with a league-leading 64-18 record.
It was by making the All-NBA team this past season that Booker qualified to receive the supermax from the Suns this offseason.
Phoenix then saw its season come to a disappointing conclusion with a rout at the hands of the Dallas Mavericks on Phoenix's home court in Game 7 of the Western Conference semifinals.
Now, the Suns are hoping to begin turning things back in a positive direction this offseason. With Booker's extension all set, Phoenix's attention will turn to figuring out the future of starting center Deandre Ayton, who is a restricted free agent, and the potential extension status of forward Cam Johnson.
After Phoenix hadn't won more than 39 games through Booker's first six NBA seasons, the Suns have now gone a combined 115-39 over the past two years, including the first NBA finals appearance for the organization since Charles Barkley led Phoenix there in 1993.
The Suns will hope for continued growth from Booker, who has blossomed into one of the league's elite guards during his eight seasons in the Valley of the Sun -- and, specifically, over the past two seasons playing alongside Paul.
Booker, who had scored 70 points in a game in Boston earlier in his career, had several massive games during Phoenix's playoff run two seasons ago, including scoring 47 to close out the Los Angeles Lakers on the road in Game 6 of the first round of those playoffs and back-to-back 40-point games against Giannis Antetokounmpo and the Milwaukee Bucks in the NBA finals.