fit the bill vs fill the bill

fit the bill and fill the bill both are verbs.

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

As verbs, fit the bill and fill the bill are synonyms defined as:

fit the bill and fill the bill: be what is needed or be good enough for what is required

fit the bill (verb)	fill the bill (verb)
be what is needed or be good enough for what is required	be what is needed or be good enough for what is required