Synonyms for From time to time:

adv.

now and then (adverb)
now and again, once in a while, occasionally.
once in a while (adverb)
once in a while.

adv

every now and then (adverb)
occasionally.
now and then (adverb)
at times, on occasion, now and again.
once in a while (adverb)
now and then.

n.

from time to time (noun)
now and again, now and then, occasionally, at times, on occasion, once in a while.

Other synonyms:

Other relevant words:
occasionally.