[1] The J3 promotion play-offs were held in a similar manner to the J2 playoffs, with the dates will be confirmed in November[2] Tochigi SC, Kagoshima United and Thespakusatsu Gunma were relegated to the J3 League, finishing the previous J2 League season as 18th, 19th and 20th places.
The second and final team promoted was Kochi United SC finished as runner-up and after won the relegation play-off defeated YSCC Yokohama with a aggregate of 1-3, the first team of Kochi Prefecture who play in the J League.
From the 2021 season onwards, there is no limitations on signing foreign players, but clubs could only register up to five of them for a single matchday squad.
[3] Players from J.League partner nations (Thailand, Vietnam, Myanmar, Malaysia, Cambodia, Singapore, Indonesia, and Qatar) were exempted from these restrictions.
If a match was tied in the play-offs, the team with the highest league position are declared the winner.