Which volumes are covered by Oregairu season 1 and 2? According to this news article on ANN, Oregairu is going to get a second anime season.

How many volumes have been covered by the first season? And which volumes will be animated in the second season?
The first season covers the first 6 volumes, and the second season will adapt volumes 7-11.

Source:
https://kyakka.wordpress.com/2015/06/12/oregairu-zoku-episode-12-and-13-synopses/