The Capitals had until July 1 to sign their most prized restricted free agent before other teams could tender an offer. In a release sent out Sunday, the Capitals said they would "make a significant player-related announcement."
"We now have two of maybe the top five players in the world playing on our team for many years to come," coach Bruce Boudreau said.
Backstrom was fourth in the league in scoring (101 points). The 22-year-old Swede was also second on the Caps in scoring (nine points) to Alex Ovechkin during the playoffs before the Presidents' Trophy winners were eliminated in the first round by the Montreal Canadiens.
Ovechkin will be entering the third year of a $124 million, 13-year deal. "I was thinking that I wanted to play with him," Backstrom said. "Hopefully he'll want to play with me, too. I wanted 10 years; I wanted long term. I think it's good that we're together."