Owens led the CFL in both combined yards (2,298) and receptions (94) last season and was named an East Division all-star.
He was named the league's most outstanding player in 2012 when he broke Argos legend Michael (Pinball) Clemons' record for most all-purpose yards in a single season with 3,863 and helped Toronto win the Grey Cup.
He returned a punt 83 yards for a touchdown in Toronto's season-opening 45-21 loss to Winnipeg on Thursday.
Keeping had his best season as an Argonaut in 2013, when he was named the East Division's outstanding offensive lineman. The Uxbridge, Ont., native was selected in the second round (18th overall) by the Argos in the 2005 CFL draft and was named the Argos' nominee for most outstanding rookie.
Keeping has played 131 games for Toronto, as well as nine playoff games, and was the team's staring centre for their 100th Grey Cup win at home.
"Chad and Jeff represent two key members of our football club," Argos general manager Jim Barker said in a statement. "They have both performed at a very high level for us on the field, and both have exhibited rarely found leadership qualities that are crucial to maintaining a positive culture within our locker-room. We are very happy they have committed to being Argonauts for the foreseeable future."