The ISR1 season consists of 2 stages. In the first stage, each ISR1 team plays Home-Away matches with the other 13 ISR1 teams in for a total of 26 league matches per teaqm. The second stage consists of the Championship Round and the Relegation Round. In the Championship Round, the top six teams play Home/Away matches each other twice (10 more matches per team) to determine final rankings for 2027-2028 UEFA Champions League and 2027-2028 UEFA Europa Conference League placements. In the Relegation Round, the bottom eight teams play each other a 3rd time (7 more matches per team) to determine the relegation placements. Total points are for all 33 matches. Table ranking ties are broken by (1) goal difference, (2) matches won, (3) goals scored, (4) head-to-head points, (5) head-to-head goal difference, (6) head-to-head goals scored, then (7) a playoff.

Not applicable.

At the end of the 2026-2027 ISR1 Regulation Round, the 7th and 8th place ISR1 Relegation Round teams will be relegated directly to the ISR2.