The original book series by Blanka Lipinska only consisted of three books and Netflix has now adapted and released all three, 365 Days, 365 Days:
This Day and The Next 365 Days. That would suggest that there aren’t plans for a fourth movie, but that could always change.
Netflix released The Next 365 Days in August 2022 and the ending is not as final as one might expect for the end of a trilogy.
Not only does it differ wildly from the book (which is actually a good thing, considering the book ending was highly polarizing), but it also leaves things rather open-ended between Massimo, Laura and Nacho.
As of writing this article on August 19, 2022, Netflix has not announced 365 Days 4. It doesn’t mean there won’t be another movie, but right now it doesn’t sound like there is one in the works.
The franchise has been controversial and critically panned from the start, so there isn’t necessarily a strong incentive for Netflix to keep making these films.
However, they do appear to generate a lot of views, so the streamer might decide to bankroll a fourth movie if the viewership numbers are high enough. That’s what got the two sequels made.