Preissing was signed as a undrafted free agent by the San Jose Sharks on April 4, 2003.[2] After a strong training camp with the Sharks, Preissing was a surprise inclusion on the opening night roster for the 2003–04 season. Tom played the full season with the Sharks where he had two goals and seventeen assists in 69 games. He was praised for making the step directly from college to the NHL without stopping in the AHL and was named San Jose's rookie of the year in 2004.[3][4] In the 2005–06 season, Preissing broke out, scoring 43 points in seventy-four games to have the second-highest-scoring season by a defenseman in Sharks history behind only Sandis Ozolinsh.
On July 9, 2006, Preissing and Josh Hennessy were traded by the Sharks to the Chicago Blackhawks for Mark Bell. The Hawks immediately traded the two, along with Michal Barinka and a second round draft pick in the 2008 NHL Entry Draft to the Ottawa Senators for Martin Havlat and Bryan Smolinski.[5] Tom then spent the 2006–07 season with Ottawa, recording 38 points in 80 games. He helped the Senators reach the Stanley Cup final in which they lost to the Anaheim Ducks in 5 games.
On July 2, 2007, Preissing signed a four-year, $11 million contract as an unrestricted free agent with the Los Angeles Kings.[6] In the 2007–08 season, his first with the Kings, Preissing suffered in production scoring only 24 points in 77 games. Preissing's underwhelming play continued as he was benched for four games into the early stages of the 2008–09 season.[7] After stepping up his play Preissing was then hampered by illness and upon recovery was assigned to the Kings affiliate, the Manchester Monarchs of the AHL on March 4, 2009, for the rest of the season.[8]
On July 3, 2009, Preissing was traded by the Kings, along with Kyle Quincey and a fifth round draft pick in the 2010 NHL Entry Draft, to the Colorado Avalanche for Ryan Smyth.[9] Preissing missed training camp and the start of the 2009–10 season having a scope on his right knee.[10] After a conditioning stint with Colorado's AHL affiliate, the Lake Erie Monsters, Tom made his Avalanche debut in a 8-2 loss to the Vancouver Canucks on November 14, 2009.[11] On November 29, 2009, after playing in four unimpressive games with the Avs, Preissing was placed on waivers and re-assigned back to the Monsters.[12] Despite leading the Monsters defense with 31 points in 49 games, his considerably large contract meant he was placed on waivers for the purpose of a buy out of his final year from the Avalanche on June 30, 2010.[13]