Customs Bureau vs Customs Service

Customs Bureau and Customs Service both are nouns.

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

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

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

Other synonyms of Customs Bureau include Bureau of Customs, USCB.

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