Service charge? (8)
'service charge' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for fee that I've seen before include "Charge for professional services" , "Cost" , "price" , "Money paid for professional services" , "Payment to a professional for services" .)
(Other definitions for gratuity that I've seen before include "Tip (to waiter)" , "present" .)