Fisher had 22 goals and 26 assists for 48 points last season, his seventh with the Senators.
The 27-year-old Peterborough, Ont., native played a key role in Ottawa's run to the Stanley Cup final last spring. He supplied plenty of grit at both ends of the ice and recorded 10 points (5-5) and 73 hits in 20 playoff games.
Fisher was drafted by the Senators in the second round (44th overall) of the 1998 NHL entry draft. In 384 career regular season games, he has 192 points (92-100) and 314 penalty minutes.
Fisher was nominated for the Selke Award as the NHL's top defensive forward in 2005-06. He finished third in the voting, behind Jere Lehtinen and winner Rod Brind'Amour.
Fisher, who was slated to become an unrestricted free agent next summer, will earn US$1.5 million this season. He will earn $6 million in 2008-'09, $4 million annually for three seasons after that and $3 million in 2012-'13.
Ottawa forward Dany Heatley and defenceman Wade Redden are still slated for unrestricted free agency after the upcoming season while centre Jason Spezza will be a restricted free agent.