The difference between these is very subtle. Recently a student told us that she was “next to” a grocery store when something happened, but she had also mentioned that she was in her car, driving away from the store.
A native English speaker would would have used close to in this case. Why?
Next to, while it does mean that your are close to or near something, additionally means to be in a position immediately to the side of something. Look at the photo below.
Close to can have the same meaning as next to, so you could say that the brown buildings in the photo above are next to each other, but you cannot say that the cars in the foreground are next to them.
They are close to the buildings, because they are not side by side.
As far as near and close to, these two words have the same meaning. The big difference is that you cannot use the preposition “to” with near. This is a common mistake made by English learners.
Below are some more examples to help illustrate the differences between these words.
I live next to my work. – By saying this, you mean that your office is to one side or the other of your house.
I live close to my work. – This means you live by your work. Maybe on one side or the other, maybe just a two minute walk around the corner.
I live near my work. – Same meaning as the “close to” sentence above, but without the preposition “to” needed.