There are several synonyms for the phrase "box numbers". One of the commonly used synonyms is "post office box numbers". This term refers to a sequence of digits that represents a specific post office box at a designated location. Another synonym for "box numbers" is "parcel numbers". This phrase is used to describe a unique identification code assigned to each package or parcel shipped through a courier or postal service. In addition, the term "mailbox numbers" is also commonly used. It represents the numerical series used to locate a particular mailbox in a street or residential area. Other synonyms for "box numbers" include "unit numbers" and "suite numbers". These terms are often used in commercial and residential buildings to identify a particular set of rooms or units.