Constantly , always, and conscientiously are synonyms for without fail; occasionally and uncertainty are antonyms of without fail. On this page, you will find 16 another word for without fail.
She calls her parents every weekend without fail.
He completes his morning run without fail.
The train arrives at this station at 8 a.m. without fail.
Without fail, the dog greets him at the door.
They submit their assignments on time without fail.