The Switch might have only got Disaster Report 4: Summer Memories in April, but series' developer Granzella has seemingly already begun work on the fifth game.
In a 2020 retrospective article on its official website, the end of a section about the fourth game discusses the fifth title. It's mentioned how "planning and partial prototyping" for Disaster Report 5 has already started and to "look forward" to more news in the future. Here is the message in full:
Rumors of a “5“
There might be some of you saying “All you have to say are advertisements?,” so I will share a bit about our next title.
According to information I acquired from sources I am unable to disclose, planning and partial prototyping for Disaster Report 5 seems to have already begun.
As for whether or not “Stiver Island” (Capital Island) is involved in the story this time… I’ll leave it at that for now as I’d rather not lose my job.
Please look forward to more news in the future!
As noted by Gematsu, it's not the first time Granzella has necessarily teased the fifth game, but it's the most official so far.
Disaster Report 4: Summer Memories has a lot of references to a fifth entry - including the ability to change the title screen to read "Disaster Report 5?" - so it's no surprise to hear a fifth game is on the way.
If you're interested in getting to know more about this series before the next game is officially announced, be sure to check out the fourth entry, available now on the Switch. You can also read our review.