Chosen Solution
I accidentally bought a 6s plus battery for my 6s from ifixit. Now I don’t want to eat 20 dollars shipping for the return (almost half the price came from shipping) Would the 6s+ battery fit in my 6s?
Unless you slice it to fit the 6S housing a 6s plus battery won’t fit, it’s way too big. And do not attempt slicing it, just joking, you’ll have to buy a suitable one. ;)