The antonyms for the phrase "boxes up" could include words such as unbox, unpack, unveil, expose or display. These terms indicate actions that are opposite to the act of packaging items into boxes. Instead of enclosing objects, one may choose to reveal them to the world, unbox them from their packaging or showcase them in an open space. Additionally, the phrase "boxes up" may also have connotations of limiting or confining, therefore antonyms such as expand, spread out, or loosen up could also be appropriate. Ultimately, the antonyms for "boxes up" depend on the context in which the phrase is used.