The 2019 Africa Cup of Nations in Cameroon will expand from 16 to 24 teams and be staged in June and July, the Confederation of African Football announced on Thursday.
The tournament has traditionally been held in January and February, and the CAF executive committee revealed the changes to the format following a two-day symposium in Rabat.
The 2019 event in Cameroon will be contested by 24 teams, instead of 16.
The changes were rubber-stamped by the CAF executive committee in a meeting in the Moroccan capital Rabat.
Africa's flagship sporting event has featured 16 teams since 1996.
The expansion of the tournament could create problems for Cameroon, which will host the next finals, with the Central African nation's sports minister having to deny reports that preparations were behind schedule.
The competition will continue to be held every two years, in Africa and only with African countries. Caf was considering whether to allow countries from other continents to compete - or even host the tournament.
The announcements follow a two-day symposium organised by Caf president Ahmad to discuss the state of African football.