According to an NHL source, it's a deal with a base salary of $2 million and bonuses that could push it close to $4 million if Kimonen, 39, activates them.
The structure of the deal allows the Flyers to keep the salary cap hit low, and roll any bonuses achieved into next year's cap number. It's important because Philadelphia is close to the cap and still needs to sign restricted free agent Brayden Schenn to a contract extension.
Timonen averaged over 20 minutes of icetime per game for the Flyers last season and had 35 points in 77 games. He's played 1092 games in his career.
In seven seasons with the Flyers, Timonen has won five Barry Ashbee trophies as the team's best defenseman, including the last three. He ranked second in team history behind Eric Desjardins, who won the award seven times.
He has also made two of his five Olympic appearances with Finland during his time as a Flyer, winning bronze in both 2010 and 2014. He was recognized for his 1,000th career NHL game in March 2013.
The Associated Press contributed to this report.