individually vs on an individual basis

individually and on an individual basis both are adverbs.

Word	Noun	Adjective	Verb	Adverb
individually	No	No	No	Yes
on an individual basis	No	No	No	Yes

As adverbs, individually and on an individual basis are synonyms defined as:

Other synonyms of individually include one by one, separately, severally, singly.

individually (adverb)	on an individual basis (adverb)
apart from others	apart from others