I prefer to keep it simple. If it's a story set in the future, and if it obeys natural laws*, then I call it science fiction.
If the story includes supernatural forces, like magic or vampires or dragons, then I call it fantasy.
I don't mind additonal labels like "urban fantasy" and "paranormal romance" -- they help me avoid stories I don't want to read
-- but I
really don't understand some authors' preference for the label "speculative fiction" rather than "science fiction." Puh-leese. It's science fiction, which has always been speculative.
If a story has fantasy traits then it's not "speculative fiction." Anyone can convince himself of this fact by reading the definitions of
speculation and
speculative.
*the author can specualte that future populations have a better understanding of natural laws, permitting features like faster-than-light travel, but there must be a theoretically scientific explanation.