Todd Howard says Bethesda is "in plans for future games" in the series, but isn't ready to say anything about that yet.
In an interview with Variety discussing the Fallout TV Show, Howard was asked what the success of the series might mean for new games in the universe. After all, it's been six years since Fallout 76 (which just got its new Fallout 76 Skyline Valley map) launched, and nearly a decade since the Fallout 4 marked the last traditional single-player entry.
In response to that question, Howard admitted that while he feels "like it took us 15 years from its initial inception" despite only taking five years, that's how long it takes to make a modern Bethesda game. The studio is "in plans for future games in this series," he says, but with Starfield less than a year old and The Elder Scrolls 6 next on the docket, there's "nothing to talk about right now."
It's widely understood that the next Fallout game will be Fallout 5, though whether it releases under that name remains to be seen. In fact, several major factors remain almost entirely unknown about the future of the Fallout franchise beyond the existence of Fallout Season 2. Last we heard, Bethesda developer Emil Pagliarulo told fans that "we need time to make great stuff," but that time is likely to stretch towards ten years at this point. Right now, I'm not hoping to see Fallout 5 this side of 2030, even if Howard does say Bethesda is "always planning."
One thing we do know is that Fallout 5 and beyond will "predominantly" be set in the US.