The 38-year-old forward announced Sept. 2 he was taking some time away from the NHL.
"Because of my current indecision and without the type of mental and physical commitment that I'm accustomed to having, I've decided to step away from the game," Williams said at the time.
Williams was in attendance at PNC Arena for a 5-4 overtime win against the Philadelphia Flyers on Tuesday.
"There's no adjustment because we know what he is," Carolina coach Rod Brind'Amour said. "He's been here, he's a Hurricane. It would be an adjustment for him to just get back up to speed. He's been out a long time. We would obviously welcome him back. This will be a huge addition for us."
Williams, who was captain of the Hurricanes last season, his 18th in the NHL, had 53 points, including ranking second on Carolina with 23 goals, in 82 regular-season games and had seven points (four goals, three assists) in 15 Stanley Cup Playoff games to help the Hurricanes reach the Eastern Conference Final in their first postseason appearance since 2009.
"We've been in frequent contact with Justin over the last few months regarding his status," Carolina general manager Don Waddell said. "We're thrilled that he has decided to return to playing, and we're confident that adding him to our group will help us both on and off the ice."
Selected by the Philadelphia Flyers in the first round (No. 28) of the 2000 NHL Draft, Williams has 786 points (312 goals, 474 assists) in 1,244 games with the Flyers, Hurricanes, Los Angeles Kings and Washington Capitals. He has 101 points (40 goals, 61 assists) in 155 NHL playoff games, winning the Stanley Cup with the Hurricanes in 2006 and the Kings in 2012 and 2014.
The Hurricanes (25-16-2), who are the first wild card into the Stanley Cup Playoffs from the Eastern Conference, next play when they host the Arizona Coyotes on Friday (7:30 p.m. ET; ESPN+, FS-CR, FS-A PLUS, NHL.TV).
