service agency vs service firm

service agency and service firm both are nouns.

Word	Noun	Adjective	Verb	Adverb
service agency	Yes	No	No	No
service firm	Yes	No	No	No

As nouns, service agency and service firm are synonyms defined as:

service agency and service firm: a business that makes its facilities available to others for a fee; achieves economy of scale

Other synonyms of service agency include service bureau.

service agency (noun)	service firm (noun)
a business that makes its facilities available to others for a fee; achieves economy of scale	a business that makes its facilities available to others for a fee; achieves economy of scale