The term 'not later than' is a phrase used to indicate a deadline or a time limit. It is often used in contracts and other legal documents. The two crossword solutions for this term are 'BY' (2 letters) and 'UNTIL' (5 letters). BY is used to indicate the point in time at which something must be done, while UNTIL is used to indicate the point in time at which something must be completed. Together, these two words form the phrase 'not later than, ' which is used to indicate a deadline or time limit.