SZA needs to be way more careful when she's scoping out a new pad ... because you never know when an open door to a down staircase will appear.
The singer and her friend, Sage, were in their new house getting some video for their Instagram stories when SZA -- clearly unfamiliar with the lay of the land -- takes a nasty fall.
Check it out ... her friend's recording when SZA squats down, apparently thinking she's still got a wall behind her and leans back too far into the abyss.
It looks pretty bad, but Sage -- despite screaming in horror -- keeps filming and we see SZA at the bottom of the steps ... and she says she's fine.
Probably not the best way to get settled into a new home, but a memorable way ... as long as she didn't hit her head too hard.