CONCACAF, the governing body for football in North America, Central America and the Caribbean, said in a statement that the club tournament would increase from 16 to 27 teams after the 2023 tournament.
Eighteen teams participating in the competition will come from North America, with as many as nine sides from the United States and Canada potentially able to qualify.
Under the new format, 22 teams will play in 11 home-and-away first round games, with five other teams automatically advancing to the last 16.
The tournament will proceed as a home-and-away knockout tournament until the final, which will be played as a single game one-off fixture.
The five teams given a bye into the last 16 will be the MLS Cup champion, the champion of Mexico’s Liga MX, and the winners of three new sub-regional club tournaments — the Leagues Cup, which features teams from MLS and Liga MX, the Central American Cup and the Caribbean Cup.
Major League Soccer is guaranteed at least five entrants under the revised format.
As well as the winners of the MLS Cup, places will also be given to the winners of the Supporters Shield, which goes to the team with the best regular season record, the conference winner opposite the Shield winner, and the two teams with the next best regular season records.
The winner of the US Open Cup — the knockout competition which features more than 100 clubs from across the United States — will also earn a berth into the first round.
The Seattle Sounders are the reigning CONCACAF Champions League winners, claiming victory over two legs last month against Mexico’s UNAM.