The contract carries a $2 million AAV ($1.75 million in 2021-22, $2.25 million in 2022-23).
"He's someone that is mobile, he's got great experience who is a great pro," Senators general manager Pierre Dorion said. "Every time we did a background check on him over the last few weeks we felt he was someone who would fit in great with this group.
"We felt that giving him this term at this dollar amount was really going to be the right fit for us."
Del Zotto has notched 249 points (60 goals) in 710 career NHL games and in 2020-21, had 13 points (four goals) in 53 games with Columbus.
The 31-year-old was part of the Blues' Stanley Cup winning team in 2018-19 and has also previously played for the New York Rangers as well Anaheim, Nashville, Philadelphia and Vancouver.
"He can mentor our younger players," Dorion said. "He's seen it all: he's a first round pick. He's had to sign a two-way contract. He's a good puck-mover and he's going to really fit in well with our team."
