Quincey played in the National Hockey League (NHL) for the Detroit Red Wings, Los Angeles Kings, Colorado Avalanche, Tampa Bay Lightning, New Jersey Devils, Columbus Blue Jackets, and the Minnesota Wild.

At the beginning of the 2003–04 season in early October, Quincey was traded from London to the Mississauga IceDogs in a blockbuster deal for star forward Rob Schremp.

He finished the season fifth among rookie defencemen in the AHL with seven goals and 33 points in 70 games, while also making his NHL debut with Detroit against the Mighty Ducks of Anaheim on November 25, 2005.

As a late call-up, he scored his first NHL goal in the last game of the Red Wings' 2006–07 regular season in a 7–2 win over the Chicago Blackhawks on April 7, 2007.

[8] Unable to crack the talent-laden Red Wings and due to salary cap compliance issues, he was placed and eventually claimed off waivers on October 13, 2008, by the Los Angeles Kings.

[11] He finished his breakthrough season leading the Kings' defence in scoring, with 34 assists and 38 points in 72 games, before finally succumbing to a herniated disc on April 1, 2009.

[12] On July 3, 2009, Quincey was traded, along with defenceman Tom Preissing and a fifth-round pick in 2010, to the Colorado Avalanche in exchange for left winger Ryan Smyth.

[15] Quincey again quickly established himself within the re-building Avalanche defence to lead the team in average ice time and to record a career-high of six goals for 29 points in 79 games.

[18] Marking his progression in returning to his original draft team in which his initially left on a waiver transaction, Quincey appeared in all 18 games and the Red Wings' first round defeat to the Nashville Predators to end the 2011–12 season.

With the Devils falling in standings and having contributed 12 points in 53 games, Quincey was traded at the deadline to the playoff-bound Columbus Blue Jackets in exchange for Dalton Prout on March 1, 2017.

On July 1, 2017, having left the Blue Jackets as a free agent, Quincey was signed to a one-year, $1.25 million contract to provide a veteran presence on the blueline with the Minnesota Wild.

[28] Upon clearing waivers, Quincey was originally assigned to the AHL with the Iowa Wild, however refused to report, he subsequently sat out for the remainder of the season.

On August 28, 2018, Quincey as a free agent signed his first contract abroad in agreeing to a one-year deal with Finnish club, HIFK of the Liiga.