The annual tournament, previously squeezed into a five or six-month schedule, will now be played from February to November, reflecting the breadth of most domestic leagues in the region, reports Xinhua.
Conmebol, South American football's governing body, announced the changes after a meeting of federation presidents in Luque, Paraguay on Tuesday.
Winners of the competition - and of the second-tier Copa Sudamericana - will now earn a direct berth in the following year's edition of the Copa Libertadores.
And just like Europe's UEFA Champions League, clubs knocked out after the Copa Libertadores group stage will now advance directly to the Copa Sudamericana.
"This will help South American football reach its potential and allow the game to grow, promoting greater sustainability among clubs and associations," Conmebol president Alejandro Dominguez said.
"For many years clubs have had to choose between giving priority to the Copa Libertadores or their national league, and that has affected the quality of both competitions."
Dominguez said another meeting in November would decide how many teams from each country would feature in the Copa Libertadores group stage.
