importantly vs significantly

importantly and significantly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
importantly	No	No	No	Yes
significantly	No	No	No	Yes

As adverbs, importantly and significantly are synonyms defined as:

importantly and significantly: in an important way or to an important degree

importantly (adverb)	significantly (adverb)
in an important way	in an important way or to an important degree
in an important way or to an important degree	in a significant manner
	in a statistically significant way