The Blazers are also traded away Larry Nance Jr. and Tony Snell to New Orleans.
In exchange, Portland will get four players: Josh Hart, Tomas Satoransky, Nickeil Alexander-Walker and Didi Louzada.
The Blazers will also get a conditional first-round draft pick and two second-round picks.
McCollum has played with the Trail Blazers since they selected him with the 10th pick in the 2013 draft.
The Blazers confirmed the trade Tuesday evening and shared several sendoff posts on social media for McCollum, thanking him for his time playing in Rip City.
The trade marks the end of an era on Portland, where McCollum has been paired with Damian Lillard in the backcourt since 2013. Portland has reached the playoffs every season since they drafted McCollum. However, the Blazers struggled in the postseason, reaching the Western Conference finals only once while being eliminated in the first round five times.
Lillard wished McCollum well in a heartfelt Instagram post.
The 30-year-old McCollum is averaging 20.5 points, 4.5 assists and 4.3 rebounds this season.
He gives the Pelicans a needed outside shooting threat at a time when New Orleans appears to be on the upswing under first-year coach Willie Green — despite playing without star forward Zion Williamson all season. After starting 1-12, the Pelicans (21-32) entered Tuesday’s games on the heels of a three-game road winning streak and occupying the final play-in spot in the Western Conference.
Williamson has been in Oregon trying to rehabilitate from offseason surgery to repair his fractured right foot. It is unclear if he will be ready to return at all this season.
New Orleans is making less than 33% from 3-point range this season and they are 29th in the league 3-pointers made. McCollum has shot no less than 37.5% from beyond the arc every season from deep in every season of his career, while shooting 38.4% overall for his career.
The news of the Tuesday trade came only days after it was announced the Blazers were parting ways with Norman Powell and Robert Covington in exchange for Eric Bledsoe, Justise Winslow, rookie Keon Johnson and a second-round pick in 2025 from the Los Angeles Clippers.