Recommendations?

So I’ve completed all of the rest of my applications on Common App but I still need my recommendations. Each college you can assign a teacher but I was just confused if my teachers fill out one recommendation and it goes to all the schools I asign them to or if they have to fill out separate ones each time I assign them to a school? Thanks in advance.

Teachers complete a single recommendation.

It’s a single rec, and they just send it to each school you ask them to.