Customs Service vs Bureau of Customs

Customs Service and Bureau of Customs both are nouns.

Word	Noun	Adjective	Verb	Adverb
Customs Service	Yes	No	No	No
Bureau of Customs	Yes	No	No	No

As nouns, Customs Service and Bureau of Customs are synonyms defined as:

Customs Service and Bureau of Customs: the agency of the Treasury Department that enforces import tariffs

Other synonyms of Customs Service include Customs Bureau, USCB.

Customs Service (noun)	Bureau of Customs (noun)
the agency of the Treasury Department that enforces import tariffs	the agency of the Treasury Department that enforces import tariffs