User blog comment:Xilinoc/Ch. 604 - REVITALIZE/@comment-3230060-20141107145024/@comment-24913480-20141107153255

Kubo has only directly refered to Hell twice in the manga: in one of the first chapters when shrieker was defeated and in promotional chapter "Imaginary Number 01". Now, I don't know how he views his version of Hell or how it connects to the rest of the Bleachverse but I suposse it is canon until mentioned otherwise.

Personaly, and based on what I know of the Bleachverse, the existence of Hell as an actual dimension makes little to no sense. The souls of dead humans either go to Soul Society or Hueco Mundo (eventually) and when they die there they are reincarnated in the Human World again (the souls exist in a cicle, I think). This cicle must remain in balance: the number of souls in one dimension cannot greatly surpass the number of souls in another dimension. With the ever increasing human population I don't know how this balance is maintained but maybe souls can also be born in Soul Society (if there are Royal Families then they are making babies there). The existence of Hell would only disrupt this balance: souls that would go to Hell probably couldn't be released (maybe) so new souls would always need to be added to the cicle to compensate the ones lost to Hell. Furthermore, what kind of soul would even go to Hell? Bad people? Humans? Hollows that weren't purified by a zanpakuto? We know there are monsters in all the dimensions but noone has ever said that bad shinigami go to Hell when they die. And good people still suffer (a LOT!) in Soul Society (the Heaven version of Bleach). Makes no sense to add yet another crapsack dimension on top of the already existing ones.

TL;DR: Considering the context in which Hell has been mentioned in the manga (in the very beginning and to promote a non canon movie) I think we should just ignore it until Kubo decides to come up with some logic for it.