The 2018–19 Phoenix Suns season was the 51st season of the franchise in the National Basketball Association (NBA), as well as their 26th season at the Talking Stick Resort Arena. They finished with 19 wins to 63 losses, the franchise's worst regular season record since the inaugural season 1968–69.

The Suns started the season with a new head coach, signing former assistant coach Igor Kokoškov to a three-year deal on May 2, 2018. After winning the first overall pick in the 2018 NBA draft, the Suns picked Deandre Ayton, a Bahamian center from the University of Arizona. They also gained the draft rights of the tenth overall pick, Mikal Bridges, through a trade involving the Philadelphia 76ers, thus recovering the final pick they received from first trading Steve Nash to the Los Angeles Lakers back in 2012. During the 2018 NBA free agency period, the Suns also acquired some key players from the Houston Rockets the previous season with Trevor Ariza on July 1 and Ryan Anderson and rookie De'Anthony Melton nearly two months later on August 31. But after failing to sign a starting-caliber point guard during free agency, general manager Ryan McDonough was fired before the regular season began on October 8. He was replaced by former Suns' player James Jones and Trevor Bukstein on an interim basis throughout the entire season; Jones was eventually named the permanent general manager after the end of this season, with Bukstein returning to his initial assistant general manager role going forward.

The Suns were the first team eliminated from playoff contention on February 23, missing the playoffs for the ninth straight season.

Key dates April 13, 2018: The NBA used a coin flip to decide whether the Suns get both Miami and Milwaukee's first-round picks this year or just Miami's first-round pick; Miami's selection ultimately became the 16th overall pick instead of Milwaukee's pick. May 2, 2018: Igor Kokoškov was confirmed to sign a three-year deal with the Suns as their next head coach. May 15, 2018: The NBA draft lottery took place, the last year of the original weighted lottery was in effect; Phoenix, for the first time in franchise history, won the first overall pick in the NBA draft lottery. June 21, 2018: The 2018 NBA draft took place at the Barclays Center in Brooklyn, New York; Deandre Ayton from the nearby University of Arizona was the franchise's first #1 pick, while the Suns also traded small forward Zhaire Smith and the Miami Heat's 2021 first round pick to the Philadelphia 76ers for two-time NCAA Champion small forward Mikal Bridges, the tenth pick in the first round. They also drafted the French point guard Élie Okobo and Colorado shooting guard George King in the second round. June 30, 2018: The Suns waived Tyler Ulis the day before his $1.5 million contract would have been guaranteed. July 1, 2018: The NBA free agency period began; Trevor Ariza agrees to a one-year deal worth $15,000,000. July 2, 2018: The Suns waived center Alan Williams and renounced their free agency rights to two-way contracts Alec Peters and Danuel House. July 6, 2018: The July moratorium ended for free agents to begin signing contracts with new teams. July 7, 2018: Shooting guard Devin Booker received a five-year maximum contract extension with the Suns. July 20, 2018: The Suns retained both guards Davon Reed and Shaquille Harrison after their 2018 NBA Summer League performances; Phoenix also made two trades: Jared Dudley (and a top-35 protected 2021 second-round pick) to the Brooklyn Nets in exchange for Darrell Arthur, and $1,000,000 in cash considerations to the Philadelphia 76ers for power forward/center Richaun Holmes. August 10, 2018: The NBA revealed every team's schedule. August 31, 2018: The Suns traded their projected starting point guard Brandon Knight and power forward Marquese Chriss to the Houston Rockets in exchange for starting power forward Ryan Anderson and rookie point guard De'Anthony Melton. September 7, 2018: Former Suns' players Charlie Scott, Jason Kidd, Steve Nash, Grant Hill, and former Suns' president Rick Welts are all inducted in the Naismith Basketball Hall of Fame. It marks the largest number of players from one NBA team to enter the Hall of Fame. September 10, 2018: Shooting guard Devin Booker was announced to be out for up to six weeks following surgery on his right pinkie, potentially missing at least the first two or three games of the regular season. October 8, 2018: Robert Sarver abruptly fired general manager Ryan McDonough and named former Suns' player James Jones and Trevor Bukstein as the interim general managers for the rest of this season before the regular season began. October 15, 2018: The Suns waived Darrell Arthur and Shaquille Harrison to reduce the final roster for the start of the season deadline. October 17, 2018: The Suns opened the regular season with a 121–100 win over the Dallas Mavericks, with Devin Booker returning in time for action that day. December 12, 2018: Team owner Robert Sarver reportedly threatened to move the Suns after no votes for arena renovations were set up. December 17, 2018: The Suns traded Ariza for Austin Rivers and Kelly Oubre Jr. This trade came two days after a planned three-way trade with the Washington Wizards and Memphis Grizzlies fell apart through miscommunication. Rivers was then waived the following day. January 23, 2019: The Phoenix City Council approved a new renovation plan for the Talking Stick Resort Arena with a majority 6-2 vote, which includes the team building a new practice facility north of Phoenix (eventually being named the Verizon 5G Performance Center), replacing the old practice court in the arena’s basement, and remaining committed to their home arena until at least 2037. February 6, 2019: The Suns agreed to trade Ryan Anderson to the Miami Heat in exchange for Tyler Johnson and Wayne Ellington, waiving the latter player the following day. February 27, 2019: Two days after ending their franchise record 17-game losing streak, the Suns reportedly had begun searching for a permanent general manager. April 11, 2019: After the conclusion of this season, the Suns announced that James Jones will be the team's permanent general manager moving forward, with co-interim general manager Trevor Bukstein being demoted back to his prior assistant general manager role and Jeff Bower being named senior vice president of basketball operations for some future seasons at hand. May 21, 2019: Deandre Ayton is officially named a member of the NBA All-Rookie First Team for being one of the top rookies this season.

Off-season Draft picks

Round Pick Player Position(s) Nationality College / Club 1 1 Deandre Ayton C Arizona 1 10 Mikal Bridges SF Villanova 2 31 Élie Okobo PG Élan Béarnais Pau-Lacq-Orthez 2 59 George King SG Colorado

Entering the draft, the Suns had just two first-round picks and two second-round picks. Their first pick would be their own pick, which became their first ever number one pick in franchise history after 50 seasons. It came as a result of having the second-worst record in franchise history, with only their inaugural season being worse. The Suns were guaranteed just the Miami Heat's first-round pick this year due to a 2015 trade involving the brothers Dragić, with both Zoran and Goran Dragić being traded to Miami in a three-way trade including the New Orleans Pelicans in exchange for the rights to John Salmons, Danny Granger, the Heat's first-round pick this year, and Miami's completely unprotected 2021 first-round pick. Near the conclusion of the previous season, the Suns had a chance to also receive the Milwaukee Bucks' first-round pick as well, as that was projected to be included alongside Greg Monroe and a second-round pick in order to offload Eric Bledsoe, who no longer wanted to be with the Suns. However, despite Miami winning more games against Milwaukee that season, the Suns would not gain Milwaukee's first-round pick this season. However, the Suns still retained the 16th pick from the Heat, alongside their 1st pick, up until draft night.

Phoenix was also projected to have the Los Angeles Lakers' first-round pick from the Steve Nash trade of 2012, but the pick was traded to the Philadelphia 76ers to acquire Brandon Knight in 2015. The Suns regained that selection on draft night in exchange for the Miami Heat's first round selections that were previously acquired. In the second round, the Suns traded their own pick to the Memphis Grizzlies in exchange for Troy Daniels and what would be the Charlotte Hornets' second-round pick, although their own pick was kept by Phoenix due to top 55 protections placed on their own second-round pick for the second year in a row. Phoenix also gained the penultimate pick to the draft, the Toronto Raptors' second-round pick this year, after also gaining last year's second-round pick and the rights to Jared Sullinger in exchange for them briefly acquiring P. J. Tucker. In other transactions around their projected second-round picks, the Hornets' second-round pick would be traded to the Orlando Magic in exchange for Elfrid Payton, and the Bucks' second-round pick would go to the Brooklyn Nets (via a separate trade) due to it being inside the top 47.

With the top pick of the 2018 NBA Draft, the Suns selected the Bahamian freshman center Deandre Ayton from the nearby University of Arizona. While he was reported to be the #1 pick for weeks before the draft, Ayton competed with a few other players such as former high school teammate Marvin Bagley III, international superstar (and former player of new head coach Igor Kokoškov's) Luka Dončić, Jaren Jackson Jr., and Mohamed Bamba during those weeks. In his sole season playing (and starting) in 35 games for Arizona, Ayton averaged 20.1 points (on.612 overall percentage and.343 three-point percentages), 11.6 rebounds, 1.9 blocks, 1.6 assists, and 0.6 steals under 33.5 minutes per game while also being named a consensus All-American First Team, the Pac-12's Player of the Year, the Pac-12's Freshman of the Year, being a member of the All-Pac-12 First Team, winning the Pac-12 Tournament's Most Outstanding Player Award, and winning the Karl Malone Award for being considered the best power forward of the NCAA, even though he projects more as a center entering the NBA. Ayton became a standout player for the Suns almost immediately entering the season, being an immediate starter for the team and being the only rookie this season a double-double average for their rookie season, averaging 16.3 points and 10.3 rebounds throughout the season. He ended the season being a member of the NBA All-Rookie First Team, with Ayton being a key figure for the Suns' future going forward.