Yeah you can continue growing until the mid-20s but most people have stopped by about 18-21, or at least have done over 95% of any growing their gonna do
I shot up another two inches when I was about 21, so it does happen. But I think it's rare. I'm also one of the tallest people in my family but I'm not sure that has anything to do with the growth spurt.
As everyone has said, it's different for everyone. As for me, I stopped growing taller at around 18, but kept filling out throughout my 20's. Actually, I'm almost 30 now and still filling out now that I'm doing weight lifting I mean I'm heavier and bigger than I ever was before, and it's not fat!