tax benefit vs tax break

tax benefit and tax break both are nouns.

Word	Noun	Adjective	Verb	Adverb
tax benefit	Yes	No	No	No
tax break	Yes	No	No	No

As nouns, tax benefit and tax break are synonyms defined as:

tax benefit and tax break: a tax deduction that is granted in order to encourage a particular type of commercial activity

tax benefit (noun)	tax break (noun)
a tax deduction that is granted in order to encourage a particular type of commercial activity	a tax deduction that is granted in order to encourage a particular type of commercial activity