Time to call it a night
(it's) time to call it a night
It is time to stop working, either at one's job or on a particular task, for the night. When we still couldn't find the source of the discrepancy after the third pass-through, we decided it was time to call it a night. OK, the last table has left the restaurant. Time to call it a night!
Time to call it a night.
It's time to quit one's activities for the night. (Can refer to work or partying.) Bob: Wow, it's late! Time to call it a night. Mary: Yes, it's really dark! Good night. Fred: Gee, I'm tired. Look at the time! Jane: Yes, it's time to call it a night.