Per Tim Reynolds of the Associated Press, the deal is worth $30 million.
The 30-year-old averaged 10.5 points on 40.1 percent shooting, 5.9 rebounds and 1.1 steals per game last season for the Memphis Grizzlies and Miami Heat. The Grizz traded him to the Heat as part of a three-team swap with the Minnesota Timberwolves in February.
Crowder played an integral part in the Heat rotation en route to their Eastern Conference title, averaging 31.4 minutes per night during the playoffs, when he started all 21 games. The 6'6" small forward notably brought an improved three-point stroke to Miami, knocking down 44.5 percent of his threes in 20 regular-season games.
The eight-year veteran has moved on to the Suns, however, after becoming an unrestricted free agent this offseason when a five-year, $35 million contract signed with the Boston Celtics in 2015 expired.
The 2012 second-round pick out of Marquette will join the seventh team of his career in the Suns, who should benefit from his veteran experience.
After going a perfect 8-0 in the NBA bubble in Orlando, Florida, last season and barely missing the postseason play-in game, the Suns have made some big moves this offseason in an attempt to end their 10-year playoff drought.
With a core of Paul, Devin Booker and Deandre Ayton to go along with a supporting cast that includes Mikal Bridges and Crowder, the Suns will be a trendy pick to do damage in the Western Conference next season.