Demers had nine goals and 29 points last season, his first with the Panthers after signing a five-year, $22.5-million contract.
“We are very pleased to add Jason to our blue line corps,” said Coyotes general manager John Chayka in a release. “Jason is a skilled right-handed shot defenceman who moves the puck well and has good offensive ability.
“He will be a great addition to our team.”
The Panthers will retain 12.5 per cent of Demers’ salary for the remaining for years, leaving the Coyotes responsible for a cap hit just under $4 million for the next four seasons.
McGinn had nine goals and 17 assists in 72 games last season and is signed through the 2018-19 season at a $3.33-million cap hit.
“Jamie brings size, skill and grit to our lineup and makes us a tougher team to play against,” said Panthers GM Dale Tallon in a release. “He’s played in over 500 NHL games and possesses a strong game on both sides of the puck.
“Jamie will be a welcome addition to our club as we move forward through training camp and into the season.”