handling cost vs handling charge

handling cost and handling charge both are nouns.

Word	Noun	Adjective	Verb	Adverb
handling cost	Yes	No	No	No
handling charge	Yes	No	No	No

As nouns, handling cost and handling charge are synonyms defined as:

handling cost and handling charge: the cost of handling (especially the cost of packaging and mailing an order)

handling cost (noun)	handling charge (noun)
the cost of handling (especially the cost of packaging and mailing an order)	the cost of handling (especially the cost of packaging and mailing an order)