If you use them of course. My aunt said i couldnt when i lived with her because she was on septic. Then i just read in the "embarassing" post about a stray tampon that landed on the floor after missing the trash. I didnt know people threw them in the garbage.
The box says not to flush the applicator.
I have not had my toilet clog in 17 years of living on my own from flushing tampons. Not saying it doesnt happen, just hasnt happened to me.