There are 20 clubs in Ligue 2. During the course of a season, usually from August to May, each club plays the others twice, once at their home stadium and once at that of their opponents, for a total of 38 games. Teams receive three points for a win and one point for a draw. No points are awarded for a loss. Teams are ranked by total points, then goal difference, and then goals scored. At the end of each season, the club with the most points is crowned champion and promoted to Ligue 1. If points are equal, the goal difference and then goals scored determine the winner. If still equal, teams are deemed to occupy the same position. If there is a tie for the championship or for relegation, a play-off match at a neutral venue decides rank. The second-place finisher are also promoted to the first division. The fourth and fifth-place finishers play a one leg fixture at the fourth-place finisher's stadium, the winner of this fixture faces the third-place finisher at the third-place finisher's stadium, the winner of this fixture plays the 18th-placed team in Ligue 1 for the right to play in Ligue 1 the following season. The three lowest placed teams are relegated to the Championnat National and the top three teams from National are promoted in their place. While a decision was originally made that during the 2015–16 season only the best two teams would be promoted to Ligue 1 and the last two teams would be relegated to the National, that decision was later overturned by an appeal to the Conseil d'Etat and the French Football Federation.

In December 2021, the majority of LFP member clubs, including Championnat National club leaders, voted to contract Ligue 2 from 20 to 18 clubs for the 2024–25 season. This will happen one year after Ligue 1 itself drops from 20 to 18 teams for the 2023–24 season. The plan is for Ligue 2 to relegate four clubs to, and promote two from, National at the end of 2023–24.