til now vs up to now

til now and up to now both are adverbs.

Word	Noun	Adjective	Verb	Adverb
til now	No	No	No	Yes
up to now	No	No	No	Yes

As adverbs, til now and up to now are synonyms defined as:

til now and up to now: used in negative statement to describe a situation that has existed up to this point or up to the present time

Other synonyms of til now include as yet, heretofore, hitherto, so far, thus far, until now, yet.

til now (adverb)	up to now (adverb)
used in negative statement to describe a situation that has existed up to this point or up to the present time	used in negative statement to describe a situation that has existed up to this point or up to the present time
	prior to the present time