The U15 Number One Cup 2026 will feature 20 teams divided into 4 groups of 5, with each team playing 4 group-stage matches (1 x 35 minutes). After the group stage, teams will be placed into knockout brackets based on their final standings: 1st place teams compete for 1st–4th, 2nd for 5th–8th, and so on down to 17th–20th. Draws in knockout matches will be decided by 3 penalties per team, followed by sudden death if needed. Group rankings will be determined by points, head-to-head result, goal difference, goals scored, goals conceded, and penalties as a last resort.