fill the bill vs fulfil

fill the bill and fulfil both are verbs.

Word	Noun	Adjective	Verb	Adverb
fill the bill	No	No	Yes	No
fulfil	No	No	Yes	No

As verbs, fulfil is a hypernym of fill the bill; that is, fulfil is a word with a broader meaning than fill the bill:

Other hypernyms of fill the bill include conform to, fill, fit, fulfill, meet, satisfy.

fill the bill (verb)	fulfil (verb)
be what is needed or be good enough for what is required	fill, satisfy or meet a want or need or condition or restriction
	put in effect
	meet the requirements or expectations of