[1] All sixteen teams then progressed to a play-off stage; the top four teams in each conference advanced to the title play-offs and the bottom four teams in each conference to the 9th-place play-offs, which determined the final positions for the season.

The title play-offs doubled up as the All-Japan Rugby Football Championship, which would no longer include university teams.

[3] The following teams took part in the 2018 Top League competition: The current standings for the 2018 Top League First Stage Red Conference are: The 2018 Top League First Stage Red Conference fixtures are:[4]

The current standings for the 2018 Top League First Stage White Conference are: The 2018 Top League First Stage White Conference fixtures are:[4]

The final standings for the 2018 Top League were: The four quarter final winners qualified for the semi-finals, while the losers qualified for the 5th-place semi-finals.