at the latest
No later than a certain time. I need that report by Monday at the latest. Mom told me that she'll make a decision by this weekend at the latest.
at the latest
not beyond the time mentioned. Please pay this bill in ten days at the latest. I'll be home by midnight at the latest.
at the latest
No later than. For example, We have to be in New York by Monday at the latest. This idiom was first recorded in 1884.
at the latest
No later than: Have it done by Tuesday at the latest.