The Suns were one of two franchises to join the NBA at the start of the 1968-69 season, alongside the Milwaukee Bucks. They were the first major professional sports franchise in the state of Arizona.

With rookie Alvan Adams fortifying the center position, and with new addition Paul Westphal and Dick Van Arsdale providing the scoring punch, the Suns reached the 1976 NBA Finals, in what is considered to be one of the biggest upsets in NBA history. However, they were defeated by the Boston Celtics 4 games to 2.

Connie "the Hawk" Hawkins spent four seasons with the Suns (1969-1973) and was an All-Star each of those seasons. Despite being unable to play in the NBA when he was in his prime (due to accusations of point-shaving), Hawkins' performances throughout the ABL, ABA and NBA helped get him get inducted into the Naismith Memorial Basketball Hall of Fame in 1992.

In 1992, Paul Westphal succeeded Cotton Fitzsimmons as head coach of the Suns. With players such as Kevin Johnson, Dan Majerle, rookie Richard Dumas and the newly acquired Charles Barkley and Danny Ainge, the Suns made it to the NBA Finals in Westphal's first season, losing to the Chicago Bulls in six games. While the Suns made it to the playoffs every year under Westphal, they did not return to the Finals, and Westphal was let go during the 1995-96 season. He finished his tenure as head coach with a regular season record of 191-88 and a franchise best .685 winning percentage.

On November 10, 1990, the Suns routed the Denver Nuggets 173-143 to tie a record held by the 1959 Boston Celtics for the most points scored in a non-overtime game. The Suns had 107 points in the first half, breaking the mark of 90 set by the Nuggets three days earlier in a 161-153 loss to San Antonio.

Point guard Ron Lee, nicknamed the "Kamikaze Kid", was named to the 1977 NBA All-Rookie Team and led the NBA in steals the following season (1977-78), setting a franchise record with 225 steals.

Power forward Charles Barkley's physical size and skills ultimately earned him the nicknames "The Round Mound of Rebound" and the "Crisco Kid".

On March 24, 2017, against the Boston Celtics, shooting guard Devin Booker became the sixth player in NBA history to score 70 points in a game, joining Wilt Chamberlain, David Robinson, David Thompson, Elgin Baylor and Kobe Bryant. It was the 11th 70-point game in NBA history. Booker finished 21-of-40 shooting overall, including 4-of-11 on 3-pointers, and 24-of-26 from the free throw line. The Suns' previous scoring record was held by Tom Chambers with 60 points on March 24, 1990.

On April 9, 2019, in a 120-109 season finale loss to the Dallas Mavericks, Jamal Crawford made NBA history by recording 51 points at 39 years old and 20 days. He broke two NBA records: the oldest player to tally 50+ points--previously held by Michael Jordan at 38 years and 315 days--as well as the most points scored by a player not in the starting lineup, previously held by Nick Anderson with 50 points.

Named by ESPN in 2006 as the ninth-greatest point guard of all time, Steve Nash led the league in assists and free throw percentage at various points in his career, including 2009-10 when he had a franchise-best .938 free throw percentage.