Fill the bill! (6)
I believe the answer is:
charge
This clue is a double definition.
'fill' is the first definition.
(charging is a kind of filling)
'the bill' is the second definition.
(thesaurus)
(Other definitions for charge that I've seen before include "impeachment" , "Lord Cardigan's order to his brigade" , "Impose fee on" , "Keeping" , "Demand price; accuse" .)